Children's verbal working memory: relative importance of storage, general processing speed, and domain-general controlled attention

The Effect of Background Noise, Bilingualism, Socioeconomic Status, and Cognitive Functioning on Primary School Children's Narrative Listening Comprehension

PURPOSE

This study focuses on 7- to 9-year-old children attending primary school in Swedish areas of low socioeconomic status, where most children's school language is their second language. The aim was to better understand what factors influence these children's narrative listening comprehension both in an ideal listening condition (in quiet) and for the primary school classroom, a typical listening condition (with multitalker babble noise).

METHOD

A total of 86 typically developing 7- to 9-year-olds performed a narrative listening comprehension test (Lyssna, Förstå och Minnas [LFM]; English translation: Listen, Comprehend, and Remember) in two listening conditions: quiet and multitalker babble noise. They also performed the crosslinguistic nonword repetition test and a digit span backwards (DSB) test. A predictive statistical model including these factors, the children's degree of school language exposure, parental education level, and age was derived.

RESULTS

Listening condition had the strongest predictive value for LFM performance, followed by school language exposure and nonword repetition accuracy. Parental education level was also a significant predictor. There was a significant three-way interaction effect between listening condition, age, and DSB performance.

CONCLUSIONS

Multitalker babble noise has a negative effect on children's narrative listening comprehension. The effect of multitalker babble noise could be explained by age differences in the ability to allocate working memory capacity during the narrative listening comprehension task, suggesting that younger children may be more vulnerable for missing information when listening in background noise than their older peers.

SUPPLEMENTAL MATERIAL

https://doi.org/10.23641/asha.25209248.

Does Movement Contextually Cue Attention During Novel Word Exposure? A Comparison of Preschool Children With Developmental Language Disorder and With Typical Language

PURPOSE

This study investigated the attentional tendencies of preschool children with developmental language disorder (DLD) and their typical language (TL) peers during a word learning task to examine what visual properties of novel objects capture their attention.

METHOD

Twelve children with DLD and 12 children with TL completed a novel name extension task in which they selected which of three visual characteristics of referent objects (i.e., movement, color, pattern) was relevant during novel word-novel referent pairings. No visual feature was more relevant than the others; consequently, there were no correct and no incorrect responses.

RESULTS

Children with DLD were systematically different from their TL peers in which visual features of objects they attended to during nonword-novel referent pairings in that they selected movement as the relevant feature of novel objects more often than TL children. There was also a significant negative correlation between chronological age and the propensity for movement selections.

CONCLUSIONS

In most cases, word learning involves mapping the auditory signal onto visual information. Identifying what children with DLD naturally attend to when exposed to novel word-novel referent pairings is an important first step in order to better understand how to design effective and efficient word learning interventions with this population.

Online Comprehension of Verbal Number Morphology in Children With Developmental Language Disorder: An Eye-Tracking Study

PURPOSE

Previous studies have raised the possibility of preserved language comprehension in children with developmental language disorder (DLD) in online tasks and within simple sentence structures. Consequently, we evaluated the capacity of children with DLD to comprehend verbal number agreement in simple sentence structures (i.e., verb-object-subject and verb-subject).

METHOD

Using an eye-tracking methodology, we conducted two psycholinguistic experiments with 96 Spanish- and Catalan-speaking participants. The sample was distributed into four groups: 24 children with DLD (age range: 4;6-12;6 [years;months]; average age = 7;8 [years;months]), 24 children with the same chronological age (4;6-12;2, 7;8), 24 children with the same linguistic level (4;6-9;4, 6;8), and 24 university students as language experts (18-30, 22;5).

RESULTS

The experimental data indicate that children with DLD can comprehend verbal number agreement at least under the present experimental conditions.

CONCLUSION

The empirical outcomes suggest that number morphology comprehension by children with DLD might be more typical than what it is generally considered to be.

Speech Perception in Noise Predicts Oral Narrative Comprehension in Children With Developmental Language Disorder

We examined the relative contribution of auditory processing abilities (tone perception and speech perception in noise) after controlling for short-term memory capacity and vocabulary, to narrative language comprehension in children with developmental language disorder. Two hundred and sixteen children with developmental language disorder, ages 6 to 9 years (Mean = 7; 6), were administered multiple measures. The dependent variable was children's score on the narrative comprehension scale of the Test of Narrative Language. Predictors were auditory processing abilities, phonological short-term memory capacity, and language (vocabulary) factors, with age, speech perception in quiet, and non-verbal IQ as covariates. Results showed that narrative comprehension was positively correlated with the majority of the predictors. Regression analysis suggested that speech perception in noise contributed uniquely to narrative comprehension in children with developmental language disorder, over and above all other predictors; however, tone perception tasks failed to explain unique variance. The relative importance of speech perception in noise over tone-perception measures for language comprehension reinforces the need for the assessment and management of listening in noise deficits and makes a compelling case for the functional implications of complex listening situations for children with developmental language disorder.

Cognitive Processes Related to Memory Capacity Explain Nearly All of the Variance in Language Test Performance in School-Age Children With and Without Developmental Language Disorder

The purpose of this study was to investigate the dimensionality of the cognitive processes related to memory capacity and language ability and to assess the magnitude of the relationships among these processes in children developing typically (TD) and children with developmental language disorder (DLD). Participants were 234 children between the ages of 7;0 and 11;11 (117 TD and 117 DLD) who were propensity matched on age, sex, mother education and family income. Latent variables created from cognitive processing tasks and standardized measures of comprehension and production of lexical and sentential aspects of language were tested with confirmatory factor analysis (CFA) and structural regression. A five-factor CFA model that included the constructs of Fluid Intelligence, Controlled Attention, Working Memory, Long-Term Memory for Language Knowledge and Language Ability yielded better fit statistics than two four-factor nested models. The four cognitive abilities accounted for more than 92% of the variance in the language measures. A structural regression model indicated that the relationship between working memory and language ability was significantly greater for the TD group than the DLD group. These results are consistent with a broad conceptualization of the nature of language impairment in older, school-age children as encompassing a dynamic system in which cognitive abilities account for nearly all of the variance in linguistic abilities.

Attentional shifting in children with developmental language disorder: A meta-analysis

PURPOSE

A meta-analysis investigating attentional shifting in children with developmental language disorder (DLD) was conducted. Task type, participant age, and dependent variable metric were examined as significant moderators.

METHOD

A systematic literature review identified 20 studies that met the following inclusionary criteria:(a) were published between 1994-2018; (b) included children with DLD aged 3;00 to 17;11 years; and (c) used behavioral performance-based measures of attentional shifting.

RESULTS

Children with DLD performed poorer than age-matched peers with typically developing language (TL) by 0.42 SD across attentional shifting studies. Moderator analyses showed an effect of task type, as children with DLD performed comparatively poorer on set-shifting (g = -.52) but not alternating tasks (g = -.18). Neither age nor dependent variable used to measure attentional shifting were significant moderators.

DISCUSSION

Children with DLD exhibit deficits in attentional shifting relative to same-age peers. Results of moderator analyses reveal that deficits were found on set-shifting but not alternating tasks and that these deficits remained consistent whether researchers measure accuracy or response time switch costs to ascertain attentional shifting ability. In addition, moderator analysis results suggest that attentional shifting deficits are consistent in preschool-age and school-age children with DLD.

The use of attention to maintain information in working memory: A developmental investigation of spontaneous refreshing in school-aged children

The capacity of working memory is limited and undergoes important developmental changes during childhood. One proposed reason for the expansion of working memory capacity during childhood is the emergence and increased efficiency of active maintenance mechanisms, such as that of refreshing. Refreshing is a proposed mechanism to keep information active in working memory by bringing memory items back into the focus of attention. One prevalent view is that the spontaneous use of refreshing emerges around the age of 7 and becomes more efficient during middle childhood and beyond. Using a novel approach to examine refreshing in children in Experiment 1, we show, against common conceptions, that simply giving free time in a basic working memory task does not lead to spontaneous refreshing in 9-12-year-old children. Instead, their focus of attention appears to linger on the last-presented memory item, even when ample time for refreshing is provided. Experimentally imposing the use of refreshing in Experiment 2, however, showed that children in this age range are able to switch their focus of attention away from the last-presented item in switch to another memory item. Thus, the current study uncovers that children in middle childhood do not always spontaneously switch attention away from the last-presented memory item to refresh the entire list, even though they are able to switch attention away from the last-presented memory item when instructed to do so. The theoretical implications of these findings are discussed.

Auditory processing in children: Role of working memory and lexical ability in auditory closure

We examined the relationship between cognitive-linguistic mechanisms and auditory closure ability in children. Sixty-seven school-age children recognized isolated words and keywords in sentences that were interrupted at a rate of 2.5 Hz and 5 Hz. In essence, children were given only 50% of speech information and asked to repeat the complete word or sentence. Children’s working memory capacity (WMC), attention, lexical knowledge, and retrieval from long-term memory (LTM) abilities were also measured to model their role in auditory closure ability. Overall, recognition of monosyllabic words and lexically easy multisyllabic words was significantly better at 2.5 Hz interruption rate than 5 Hz. Recognition of lexically hard multisyllabic words and keywords in sentences was better at 5 Hz relative to 2.5 Hz. Based on the best fit generalized “logistic” linear mixed effects models, there was a significant interaction between WMC and lexical difficulty of words. WMC was positively related only to recognition of lexically easy words. Lexical knowledge was found to be crucial for recognition of words and sentences, regardless of interruption rate. In addition, LTM retrieval ability was significantly associated with sentence recognition. These results suggest that lexical knowledge and the ability to retrieve information from LTM is crucial for children’s speech recognition in adverse listening situations. Study findings make a compelling case for the assessment and intervention of lexical knowledge and retrieval abilities in children with listening difficulties.

Masked Speech Recognition in School-Age Children

Children who are typically developing often struggle to hear and understand speech in the presence of competing background sounds, particularly when the background sounds are also speech. For example, in many cases, young school-age children require an additional 5- to 10-dB signal-to-noise ratio relative to adults to achieve the same word or sentence recognition performance in the presence of two streams of competing speech. Moreover, adult-like performance is not observed until adolescence. Despite ample converging evidence that children are more susceptible to auditory masking than adults, the field lacks a comprehensive model that accounts for the development of masked speech recognition. This review provides a synthesis of the literature on the typical development of masked speech recognition. Age-related changes in the ability to recognize phonemes, words, or sentences in the presence of competing background sounds will be discussed by considering (1) how masking sounds influence the sensory encoding of target speech; (2) differences in the time course of development for speech-in-noise versus speech-in-speech recognition; and (3) the central auditory and cognitive processes required to separate and attend to target speech when multiple people are speaking at the same time.

Parent-rating vs performance-based working memory measures: Association with spoken language measures in school-age children

Working memory (WM) assessment is often part of cognitive-linguistic test batteries. The author examined the relationship between parent rating of WM functioning and children's performance-based WM, and the relationship of each with receptive and expressive spoken language measures. Study participants were eighty-three 7- to 11-year-old children. The sample represented a broad range of cognitive abilities. No participating child had frank neurological or intellectual disabilities, autism, fluency disorder, or hearing loss. Parents completed a standardized executive function rating scale that included a WM subscale. Children completed a standardized WM task and an experimental WM task. Children also completed six standardized language measures. Results showed that there was no correlation between parent rating and either of the performance-based WM tasks as well as the composite WM performance score. Parent rating of WM functioning was not related to any of the language scores whereas the composite WM performance score showed significant links with language abilities. Although parent rating and performance-based WM measures are designed to reflect the same cognitive construct, they are not correlated. Potential reasons for the findings and implications of using parent-rating and performance-based WM measures in school-age children are discussed.

Working Memory and Auditory Processing in School-Age Children

Purpose

Our goal is to present the relationships between working memory (WM) and auditory processing abilities in school-age children.

Review and Discussion

We begin with an overview of auditory processing, the conceptualization of auditory processing disorder, and the assessment of auditory processing abilities in children. Next, we describe a model of WM and a model of auditory processing followed by their comparison. Evidence for the relationships between WM and auditory processing abilities in school-age children follows. Specifically, we present evidence for the association (or lack thereof) between WM/attention and auditory processing test performance.

Clinical Implications

In conclusion, we describe a new framework for understanding auditory processing abilities in children based on integrated evidence from cognitive science, hearing science, and language science. We also discuss clinical implications in children that could inform future research.

Children's Speech Perception in Noise: Evidence for Dissociation From Language and Working Memory

PURPOSE

We examined the association between speech perception in noise (SPIN), language abilities, and working memory (WM) capacity in school-age children. Existing studies supporting the Ease of Language Understanding (ELU) model suggest that WM capacity plays a significant role in adverse listening situations.

METHOD

Eighty-three children between the ages of 7 to 11 years participated. The sample represented a continuum of individual differences in attention, memory, and language abilities. All children had normal-range hearing and normal-range nonverbal IQ. Children completed the Bamford-Kowal-Bench Speech-in-Noise Test (BKB-SIN; Etymotic Research, 2005), a selective auditory attention task, and multiple measures of language and WM.

RESULTS

Partial correlations (controlling for age) showed significant positive associations among attention, memory, and language measures. However, BKB-SIN did not correlate significantly with any of the other measures. Principal component analysis revealed a distinct WM factor and a distinct language factor. BKB-SIN loaded robustly as a distinct 3rd factor with minimal secondary loading from sentence recall and short-term memory. Nonverbal IQ loaded as a 4th factor.

CONCLUSIONS

Results did not support an association between SPIN and WM capacity in children. However, in this study, a single SPIN measure was used. Future studies using multiple SPIN measures are warranted. Evidence from the current study supports the use of BKB-SIN as clinical measure of speech perception ability because it was not influenced by variation in children's language and memory abilities. More large-scale studies in school-age children are needed to replicate the proposed role played by WM in adverse listening situations.

The role of nonverbal working memory in morphosyntactic processing by children with specific language impairment and autism spectrum disorders

BACKGROUND

Both children with autism spectrum disorders (ASD) and children with specific language impairment (SLI) have been shown to have difficulties with grammatical processing. A comparison of these two populations with neurodevelopmental disorders was undertaken to examine similarities and differences in the mechanisms that may underlie grammatical processing. Research has shown that working memory (WM) is recruited during grammatical processing. The goal of this study was to examine morphosyntactic processing on a grammatical judgment task in children who varied in clinical diagnosis and language abilities and to assess the extent to which performance is predicted by nonverbal working memory (WM). Two theoretical perspectives were evaluated relative to performance on the grammatical judgment task-the "working memory" account and the "wrap-up" account. These accounts make contrasting predictions about the detection of grammatical errors occurring early versus late in the sentence.

METHODS

Participants were 84 school-age children with SLI (n = 21), ASD (n = 27), and typical development (TD, n = 36). Performance was analyzed based on diagnostic group as well as language status (normal language, NL, n = 54, and language impairment, LI, n = 30). A grammatical judgment task was used in which the position of the error in the sentence (early versus late) was manipulated. A visual WM task (N-back) was administered and the ability of WM to predict morphosyntactic processing was assessed.

RESULTS

Groups differed significantly in their sensitivity to grammatical errors (TD > SLI and NL > LI) but did not differ in nonverbal WM. Overall, children in all groups were more sensitive and quicker at detecting errors occurring late in the sentence than early in the sentence. Nonverbal WM predicted morphosyntactic processing across groups, but the specific profile of association between WM and early versus late error detection was reversed for children with and without language impairment.

CONCLUSIONS

Findings primarily support a "wrap up" account whereby the accumulating sentence context for errors positioned late in the sentence (rather than early) appeared to facilitate morphosyntactic processing. Although none of the groups displayed deficits in visual WM, individual differences in these nonverbal WM resources predicted proficiency in morphosyntactic processing.

Developmental improvement in strategies to maintain verbal information in working memory

Although it has been proposed that maintenance of verbal information in adults’ working memory relies on two strategies, articulatory rehearsal and attentional refreshing, little is known about the interplay of these strategies in children. To examine strategy changes around the age of seven, children were asked to maintain digits during a retention interval introduced between encoding and recall. In Experiment 1, this interval was either unfilled in a delayed span task or filled with an attention-demanding task in a Brown-Peterson task. This concurrent task was either silent or aloud to vary the availability of rehearsal. Experiment 2 introduced variation in the attentional demand of the concurrent task, and an independent concurrent articulation. As predicted, recall performance was better in older children, but was reduced under concurrent articulation or when attention was less available, bringing further evidence in favor of two maintenance strategies. Moreover, the measure of the availability of attention for refreshing was correlated with recall performance in eight- and seven-year-olds, though only when rehearsal was impeded for seven-year-olds, but it did not correlate with six-year-olds’ recall. This could suggest that rehearsal is the default strategy in young children who can adaptively switch to refreshing when articulatory processes are unavailable.

The Mid-Career Award

Working memory is an extremely influential concept within experimental psychology, with, at the time of writing, over 90 papers with this term in their title published in this journal alone since 2000. One reason for this interest is that measures of working memory tend to be strong correlates of important indices of real-world function. In addition, at first sight working memory appears to be a relatively simple concept to understand. However, despite this apparent simplicity, explaining working memory performance is not straightforward. In this paper I address this challenge, with a particular focus on the development of working memory performance in children; both children developing typically and those experiencing atypical development. I specifically highlight the multiple constraints on working memory performance, and how these constraints inter-relate. I then consider the broader theoretical implications of each of these constraints for current accounts of working memory and its development.

Exploring Expressive Vocabulary Variability in Two-Year-Olds: The Role of Working Memory

PURPOSE

This study explored whether measures of working memory ability contribute to the wide variation in 2-year-olds' expressive vocabulary skills.

METHOD

Seventy-nine children (aged 24-30 months) were assessed by using standardized tests of vocabulary and visual cognition, a processing speed measure, and behavioral measures of verbal working memory and phonological short-term memory.

RESULTS

Strong correlations were observed between phonological short-term memory, verbal working memory, and expressive vocabulary. Speed of spoken word recognition showed a moderate significant correlation with expressive vocabulary. In a multivariate regression model for expressive vocabulary, the most powerful predictor was a measure of phonological short-term memory (accounting for 66% unique variance), followed by verbal working memory (6%), sex (2%), and age (1%). Processing speed did not add significant unique variance.

CONCLUSIONS

These findings confirm previous research positing a strong role for phonological short-term memory in early expressive vocabulary acquisition. They also extend previous research in two ways. First, a unique association between verbal working memory and expressive vocabulary in 2-year-olds was observed. Second, processing speed was not a unique predictor of variance in expressive vocabulary when included alongside measures of working memory.

Inter-individual differences in how presentation modality affects verbal learning performance in children aged 5 to 16

This study examines inter-individual differences in how presentation modality affects verbal learning performance. Children aged 5 to 16 performed a verbal learning test within one of three presentation modalities: pictorial, auditory, or textual. The results indicated that a beneficial effect of pictures exists over auditory and textual presentation modalities and that this effect increases with age. However, this effect is only found if the information to be learned is presented once (or at most twice) and only in children above the age of 7. The results may be explained in terms of single or dual coding of information in which the phonological loop is involved. Development of the (sub)vocal rehearsal system in the phonological loop is believed to be a gradual process that begins developing around the age of 7. The developmental trajectories are similar for boys and girls. Additionally, auditory information and textual information both seemed to be processed in a similar manner, namely without labeling or recoding, leading to single coding. In contrast, pictures are assumed to be processed by the dual coding of both the visual information and a (verbal) labeling of the pictures.

Age differences in working memory updating: the role of interference, focus switching and substituting information

Working memory updating (WMU) tasks require different elements in working memory (WM) to be maintained simultaneously, accessing one of these elements, and substituting its content. This study examined possible developmental changes from childhood to adulthood both in focus switching and substituting information in WM. In addition, possible age-related changes in interference due to representational overlap between the different elements simultaneously held in these tasks were examined. Children (8- and 11-year-olds), adolescents (14-year-olds) and younger adults (mean age=22 years) were administered a numerical updating memory task, in which updating and focus switching were manipulated. As expected, response times decreased and recall performance increased with age. More importantly, the time needed for focus switching was longer in children than in adolescents and younger adults. On the other hand, substitution of information and interference due to representational overlap were not affected by age. These results suggest that age-related changes in focus switching might mediate developmental changes in WMU performance.

Role of Working Memory Storage and Attention Focus Switching in Children’s Comprehension of Spoken Object Relative Sentences

The present study evaluated a two-mechanism memory model of the online auditory comprehension of object relative (OR) sentences in 7–11-year-old typically developing children. Mechanisms of interest included working memory storage (WMS) and attention focus switching. We predicted that both mechanisms would be important for comprehension. Forty-four children completed a listening span task indexing WMS, an auditory attention focus switching task, and an agent selection task indexing spoken sentence comprehension. Regression analyses indicated that WMS and attention focus switching accuracy each accounted for significant and unique variance in the children’s OR comprehension after accounting for age. Results were interpreted to suggest that WMS is important for OR comprehension by supporting children’s ability to retain both noun phrase 1 and noun phrase 2 prior to their reactivating noun phrase 1 from memory in order to integrate it into a developing structure. Attention focus switching was interpreted to be critical in supporting children’s noun phrase 1 reactivation, as they needed to switch their focus of attention momentarily away from ongoing language processing to memory retrieval.

Task-evoked pupillometry provides a window into the development of short-term memory capacity

The capacity to keep multiple items in short-term memory (STM) improves over childhood and provides the foundation for the development of multiple cognitive abilities. The goal of this study was to measure the extent to which age differences in STM capacity are related to differences in task engagement during encoding. Children (n = 69, mean age = 10.6 years) and adults (n = 54, mean age = 27.5 years) performed two STM tasks: the forward digit span test from the Wechsler Intelligence Scale for Children (WISC) and a novel eyetracking digit span task designed to overload STM capacity. Building on prior research showing that task-evoked pupil dilation can be used as a real-time index of task engagement, we measured changes in pupil dilation while participants encoded long sequences of digits for subsequent recall. As expected, adults outperformed children on both STM tasks. We found similar patterns of pupil dilation while children and adults listened to the first six digits on our STM overload task, after which the adults' pupils continued to dilate and the children's began to constrict, suggesting that the children had reached their cognitive limits and that they had begun to disengage from the task. Indeed, the point at which pupil dilation peaked at encoding was a significant predictor of WISC forward span, and this relationship held even after partialing out recall performance on the STM overload task. These findings indicate that sustained task engagement at encoding is an important component of the development of STM.

A distributed effects perspective of dimensionally defined psychiatric disorders: and convergent versus core deficit effects in ADHD

The focus of psychiatric and psychological research has arguably shifted from brain damage and psychosis to more common forms of psychopathology that reflect extremes variants of otherwise normal cognitive and behavioral characteristics. Now, in addition to trying to understand overtly damaged brain-function (flat tire effects), we are also seeking to understand liabilities associated with non-optimized, but otherwise intact, cognitive and behavioral abilities (poor tuning effects). This shift has pushed us to evolve our investigational strategies to more broadly consider whole-brain integrated brain systems, as well as seek to develop more specific quantifiable indicators of impoverished brain function and behavior. This paper discusses such challenges in relation to dimensionally defined psychiatric disorders and presents a novel whole-brain integrated perspective of ADHD brain function pathology.