Training verbal working memory in children with mild intellectual disabilities: effects on problem-solving

This multiple case study explores the effects of a cognitive training program in children with mild to borderline intellectual disability. Experimental training effects were evaluated comparing pre-post-test changes after (a) a baseline phase versus a training phase in the same participant, (b) an experimental training versus either a no intervention phase or a control training in two pairs of children matched for cognitive profile. Key elements of the training program included (1) exercises and card games targeting inhibition, switching, and verbal working memory, (2) guided practice emphasizing concrete strategies to engage in exercises, and (3) a variable amount of adult support. The results show that both verbal working memory analyzed with the listening span test and problem-solving tested with the Raven’s matrices were significantly enhanced after the experimental trainin

Memory in autism spectrum disorder: a meta-analysis of experimental studies

To address inconsistencies in the literature on memory in Autism Spectrum Disorder (ASD), we report the first ever meta-analysis of short-term (STM) and episodic long-term (LTM) memory in ASD, evaluating the effects of type of material, type of retrieval and the role of inter-item relations. Analysis of 64 studies comparing individuals with ASD and typical development (TD) showed greater difficulties in ASD compared to TD individuals in STM (Hedges’ g=-0.53 [95%CI -0.90; -0.16], p=.005, I²=96%) compared to LTM (g=-0.30 [95%CI -0.42; -0.17], p<.00001, I²=24%), a small difficulty in verbal LTM (g=-0.21, p=.01), contrasting with a medium difficulty for visual LTM (g= -0.41, p=.0002) in ASD compared to TD individuals. We also found a general diminution in free recall compared to cued recall and recognition (LTM, free recall: g=-0.38, p<.00001, cued recall: g=-0.08, p=.58, recognition: g=-0.15, p=.16; STM, free recall: g=-0.59, p=.004, recognition: g=-0.33, p=.07). We discuss these results in terms of their relation to semantic memory. The limited diminution in verbal LTM and preserved overall recognition and cued recall (supported retrieval) may result from a greater overlap of these tasks with semantic long-term representations which are overall preserved in ASD. By contrast, difficulties in STM or free recall may result from less overlap with the semantic system or may involve additional cognitive operations and executive demands. These findings highlight the need to support STM functioning in ASD and acknowledge the potential benefit of using verbal materials at encoding and broader forms of memory support at retrieval to enhance performance

Sentence Recall in Children with Autism Spectrum Disorder

There is an age-shift in neurotypical children: younger children tend to remember information in a verbatim manner so they store item-specific surface characteristics; between nine and ten children engage in gist recall where they store meanings of presented information. The aim of the present study was to explore false memory in children with Autistic Spectrum Disorder (ASD), as some research suggests that they develop gist recall at a later age than neurotypical children. We are also interested in the role of working memory. One approach to understanding false memory creation is activation-monitoring (AM) theory. Working memory can play a role during both the activation (encoding) phase, as well as during the monitoring retrieval phase. When working memory is overloaded or suboptimal, source monitoring is compromised at the encoding phase. In this study, we tested high-functioning children with ASD on working memory capacity. In addition, simple sentences were presented to be recalled, each one followed by a short word list that contained a thematically related distractor item. If a child used gist memory to recall the sentence, they would likely substitute the target (e.g., rabbit) word with the distractor (e.g., bunny). However, if they depended on verbatim recall, the distractor would not affect sentence recall performance. Children with lower working memory scores were more likely to incorrect answers to gist questions than those with high working memory. These findings have important implications for everyday social functioning. Though debatable, working memory impairments may encourage false memories in children with ASD

Implicit sequence learning and working memory: correlated or complicated?

The relationship between implicit/incidental sequence learning and working memory motivated a series of research because it is plausible that higher working memory capacity opens a “larger window” to a sequence, allowing thereby the sequence learning process to be easier. Although the majority of studies found no relationship between implicit sequence learning and working memory capacity, in the past few years several studies have tried to demonstrate the shared or partly shared brain networks underlying these two systems. In order to help the interpretation of these and future results, in this mini-review we suggest the following factors to be taken into consideration before testing the relationship between sequence learning and working memory: 1) the explicitness of the sequence; 2) the method of measuring working memory capacity; 3) online and offline stages of sequence learning; and 4) general skill- and sequence-specific learning

Multiple Short-Term Storage: A Task to Evaluate the Coordination Function of the Executive Central

International audienceWe propose to explore more particularly one of the multiple aspects of working memory, the function of coordination of the central executive with a complex task, the double-stimuli task. This task requires the short-term maintenance of verbal information and of visuospatial information to be coordinated for the recall. The task is conceived in such way that one can ask either for the single recall of words, or for the single recall of locations, or for the recall of localized words. The double-stimuli task is studied using two methods, dual-task methodology (articulatory suppression, Moar box-tracking and standing balance position) and comparison with simple span tasks (word recall and location recall). For word recall and location recall in the double-stimuli task, we observe the classical interference effects: articulatory suppression impairs the performance on word recall without effect on location recall whereas with visuospatial interference tasks the reverse is true. A second analysis shows that when performance on the double-stimuli task (implying the maintenance of verbal material and visuospatial material at the same time) is compared with performances on short-term memory tasks (classical word span or location span using the same material), we observe a significant decrease in performance. In a third analysis a score specific to the complex task is calculated (corrected score) that takes into account the capacities of recall of words and locations. This score directly related to the capacities of coordination implied in the task is sensitive to the most attentional requirements of interference tasks. Contrary to what can be observed on the recall of locations, the standing balance position does not produce a significant decrease in performance. These results are consistent with an interpretation of the working memory according to which coordination of the subsystems is one of the functions of the central executive

Operation of cognitive memory inhibition in adults with Down syndrome: Effects of maintenance load and material

Background Cognitive inhibition is one of the executive functions; this process over memory plays a fundamental role in recalling relevant information. The aims of this study were to understand the effects of maintenance load and stimuli on the operation of cognitive inhibition over memory in working memory tasks in adults with Down syndrome. Method The study included 36 individuals with Down syndrome (mean age = 33.44 years, standard deviation = 7.54 years, 50% women) and 36 individuals with neurotypical development (mean age = 33.55 years, standard deviation = 7.52 years, 50% women). The participants performed a working memory task in which they had to solve an interference problem during the maintenance phase. Results The Down syndrome group performed worse on cognitive inhibition over memory than the neurotypical development group. Both groups had lower recall with interference and under high-load conditions. In the neurotypical development group, memory was similar with both materials. The Down syndrome group performed better with non-social stimuli than with social stimuli. Conclusions Understanding the variables that influence cognitive inhibition over memory will help in planning effective interventions for people with Down syndrome. Considering the results, special importance should be placed on work with social stimuli, at least in individuals with Down syndrome.This work received funding from Autour des Williams, Code 10.06.01.0050 to JMLF and M

Love is . . . an abstract word: the influence of phonological and semantic factors on verbal short-term memory in Williams syndrome

It has been claimed that verbal short-term memory in Williams syndrome is characterised by an over-use of phonological coding alongside a reduced contribution of lexical semantics. We critically examine this hypothesis and present results from a memory span task comparing performance on concrete and abstract words, together with a replication of a span task using phonologically similar and phonologically dissimilar words. Fourteen participants with Williams syndrome were individually matched to two groups of typically developing children. The first control group was matched on digit span and the second on vocabulary level. Significant effects were found for both the semantic and the phonological variables in the WS group as well as in the control groups, with no interaction between experimental variable and group in either experiment. The results demonstrate that, despite claims to the contrary, children and adults with WS are able to access and make use of lexical semantics in a verbal short-term memory task in a manner comparable to typically developing individuals

Cognitive processes and math performance : a study with children at third grade of basic education

The present study aims to examine the relationship between cognitive factors and mathematical achievement in primary education. Participants were 103 Portuguese third grade students, aged 8 and 9. All participants completed a battery for working memory (WMTB-C), a test of general intelligence (Raven's Progressive Color Matrices), a selective attention test (d2), and mathematical exercises (arithmetic story problems and measurement skills). Data suggested significant correlations between math performance, executive, visuo- spatial sketchpad and g factor. Our findings suggest the importance of the cognitive factors in two mathematical domains considered. In consonance with the research in this area, we conclude that working memory (WM) assumes an important role in different math curricular achievements

Computer simulations of developmental change: The contributions of working memory capacity and long-term knowledge

Increasing working memory (WM) capacity is often cited as a major influence on children’s development and yet WM capacity is difficult to examine independently of long-term knowledge. A computational model of children’s nonword repetition (NWR) performance is presented that independently manipulates long-term knowledge and WM capacity to determine the relative contributions of each in explaining the developmental data. The simulations show that (1) both mechanisms independently cause the same overall developmental changes in NWR performance; (2) increase in long-term knowledge provides the better fit to the child data; and (3) varying both long-term knowledge and WM capacity adds no significant gains over varying long-term knowledge alone. Given that increases in long-term knowledge must occur during development, the results indicate that increases in WM capacity may not be required to explain developmental differences. An increase in WM capacity should only be cited as a mechanism of developmental change when there are clear empirical reasons for doing so

A comparison of working memory profiles in HIV-infected and HIV-exposed uninfected children

A thesis submitted to the Faculty of Humanities (University of the Witwatersrand, Johannesburg), in fulfillment of the requirements for the degree of Doctor of Philosophy by thesis in the field of Psychology. University of the Witwatersrand, Johannesburg, 2015Conventional psychometric measures, such as the IQ score, have significant limitations in addressing the assessment needs of linguistically and culturally diverse communities. In response, working memory assessment has been identified as a promising alternative to these constraints. It is a better predictor of scholastic success than IQ, and is essential in the acquisition of fundamental literacy and numeracy concepts in school beginners. While there is a lot of theoretical and empirical support for working memory performance in typically developing populations, less is known about its functioning in the context of atypical development; particularly in children who are infected with, or exposed to HIV in utero. This study compared the working memory (AWMA) and general neuropsychological functioning (NEPSY-II) of 273 South African school beginners (6-8 years). The sample consisted of both HIV-infected (n = 95), and HIV-exposed (n = 86) children, as well as an uninfected, unexposed typically developing control group (n = 92). Significant differences were found between the three groups on measures of working memory and general neurocognitive functioning, where the processing component of working memory appeared to be particularly impaired in the two HIV-affected atypical groups. A within-group analysis of the relative strengths and weaknesses of each of the three groups showed that both storage and processing skills in the verbal domain appeared to be general weaknesses, while visuospatial working memory was a relative strength. The former is believed to be influenced by issues of linguistic test bias in the multilingual sample, while the latter is posited to be a consequence of this very multilingualism, which affords these children an executive functioning advantage. The two HIV-affected samples also showed significant deviations in the structure of their working memory when compared to the typically developing control group. However, within-group structural comparisons of a number of working memory models showed that the four factor model comprising separate components of the verbal and visuospatial simple and processing components of working memory was still favoured, even in conditions of atypical development. The study contributes to the growing body of working memory research by presenting the working memory profiles of HIV-infected and HIV-exposed, uninfected children. It also assists in identifying HIV-exposed, uninfected children as a vulnerable and under-researched clinical group which could benefit from further intervention, as well as foregrounding working memory as a less biased alternative in the assessment of paediatric cognitive functioning.MT201