Working Memory and Language Learning: A Review

Children with speech, language, and communication needs (SLCN) form a highly heterogeneous group including those with an unexplained delay in language development known as specific language impairment (SLI). There is growing recognition that multiple mechanisms underlie the range of profiles observed in these children. Broadly speaking, both the domain-general executive attentional system known as working memory and domain-specific linguistic processing have been implicated in children with SLI. It has been challenging to tease apart these influences, however, due to the symbiotic relationship between working memory and language learning. For example, working memory limits might constrain the linguistic detail encoded whereas poor language knowledge would place greater demands on working memory for retaining unfamiliar phonological information. There is growing evidence for separable impairments in these processing resources leading to relative deficits in linguistic or working memory processes in different children. Such findings have important clinical implications for both the assessment and treatment of children with SLCN

Morphological Awareness: Why It Makes Sense!

The smallest meaningful unit of a language is referred to as a morpheme. For example, the word ‘cups’ can be divided into two units that each bear meaning: (1) cup – a free morpheme meaning a vessel for holding liquid, and (2) final - a bound morpheme indicating plurality, or more than one. Free morphemes can occur on their own whereas bound morphemes must be affixed to a base or root word. Morphological awareness refers to the ability to consciously consider and manipulate the morphemes within words, that is, the explicit understanding of the relation between base/root words and related words with affixes. Morphological awareness has been found to predict vocabulary, reading comprehension, and spelling performance even after differences in related skills like phonological (speech sound) awareness has been taken into account. This talk reviews the concept and research related to morphological awareness, as well as assessment and intervention options targeting school age children

Developmental Language Disorder (DLD): A persistent language disorder of unknown aetiology

Speech-language pathologists (SLPs) often see children on their caseload who exhibit a persistent delay in language development for no discernable reason. Historically, there has been no consistency in the term used to describe this disorder, which has made it difficult for families to both understand and help with the problem. Recently, an international consensus agreed on the term Developmental Language Disorder (DLD) to describe this difficulty. The release of the consensus statement was paired with an international campaign aimed at raising awareness of DLD (RADLD). Canadian SLPs are invited to join discussion on the use of the term DLD

Working memory in children with developmental disorders

The aim of the present study was to directly compare working memory skills across students with different developmental disorders to investigate whether the uniqueness of their diagnosis would impact memory skills. The authors report findings confirming differential memory profiles on the basis of the following developmental disorders: Specific Language Impairment, Developmental Coordination Disorder (DCD), Attention-Deficit/Hyperactivity Disorder, and Asperger syndrome(AS). Specifically, language impairments were associated with selective deficits in verbal short-term and working memory, whereas motor impairments (DCD) were associated with selective deficits in visuospatial short-term and working memory. Children with attention problems were impaired in working memory in both verbal and visuospatial domains, whereas the children with AS had deficits in verbal short-term memory but not in any other memory component. The implications of these findings are discussed in light of support for learning

Short-term and working memory in children with specific language impairment

Investigations of the cognitive processes underlying Specific Language Impairment (SLI) have implicated deficits in the storage and processing of phonological or verbal information. This thesis reports five studies that investigated the role of short-term and working memory in children with SLI. Study 1 demonstrated SLI deficits on measures of verbal working memory, and short-term memory for verbal but not visuospatial information. Study 2 provided evidence that children with SLI perform at age-level on visuospatial working memory measures. Study 3 demonstrated slower processing in the SLI group across domains, as well as verbal storage decrements, with the greatest deficits found for tasks tapping both of these. Study 4 found SLI deficits on measures of nonword repetition in common use, with greater impairments on the task that relied to a lesser extent on short-term memory. Study 5 established more accurate recall for multisyllabic nonwords than matched single syllable lists for all groups, although the SLI group showed different patterns of phoneme retention. It is suggested that the combination of deficits in generalized processing speed and verbal storage in SLI may be expected to have a drastic and detrimental impact on learning, and provides an account of the disorder that could encompass the range of impairments observed in SLI. The findings also suggest that factors additional to short-term memory contribute to poor nonword repetition in SLI

The role of phonological and semantic representations in verbal short-term memory and delayed retention

It has been suggested that phonological representations play a central role in verbal short-term memory, but when semantic knowledge has been investigated, it has also been shown to influence verbal short-term memory. Explaining this interaction between verbal short-term memory and the linguistic system has produced different theoretical positions: whether semantic knowledge is used to redintegrate phonological traces or if there is direct activation of both phonological and semantic knowledge upon encountering a word. The present study employed a new paradigm to systematically examine phonological and semantic representations in verbal short-term memory as well as long-term impacts. Across two experiments, a list of words was presented sequentially, followed by a probe word. Participants were to judge whether the probe word rhymed or was synonymous with any items on the list. Delayed memory was also tested. In Experiment 1, we found that immediate performance was better for synonym than rhyme judgements, and this continued to be the case after a brief delay. In Experiment 2, under a fast-encoding, running-span paradigm, we found similar activation of phonological and semantic knowledge. Nevertheless, accuracy was again higher for items probed with the semantic than rhyme cue in the long term. Results showed that indeed there are short-term semantic effects, in addition to phonological effects. Further, semantic processing can occur in a highly automatic and rapid manner, with strong influence on long-term memory. These findings provide a new perspective on viewing verbal short-term memory as operating more dynamically within the context of a complex linguistic system

Cognitive and Linguistic Effects of Working Memory Training in Children With Corresponding Deficits

Working memory training has been found to result in improvements on tasks similar to those involved in the training (near transfer) but show limited impact on everyday skills such as language or academic abilities (far transfer). Previous research has largely focused on those with a broad range of skills, and examined group level responses. This study uses a single subject design to examine the effect of working memory training on both working memory and related domains in children with working memory impairment. Seven children (8–11 years old) with a working memory impairment completed 20 sessions of computerized working memory intervention. Data revealed near transfer for all participants. Evidence of far transfer to improvements in language, reading, or math was observed for approximately half of the participants on individual measures. Three participants showed convincing but modest training effects across multiple measures. A combination of factors appeared to influence far transfer including age, training intensity, and baseline measures

Cognitive and linguistic effects of narrative-based language intervention in children with Developmental Language Disorder

Background and aims: Narrative-based language intervention provides a naturalistic context for targeting overall story structure and specific syntactic goals in children with Developmental Language Disorder (DLD). Given the cognitive demands of narratives, narrative-based language intervention also has the potential to positively impact related abilities such as working memory and academic skills. Methods: Ten children (8–11 years old) with DLD completed 15 sessions of narrative-based language intervention. Results: Results of single subject data revealed gains in language for five participants, four of whom improved on a probe tapping working memory. An additional four participants improved on a working memory probe only. On standardized measures, clinically significant gains were noted for one additional participant on a language measure and one additional participant on a visuospatial working memory. Carry over to reading was noted for three participants and to math for one participant. Across measures, gains in both verbal and visuospatial working memory were common. A responder analysis revealed that improvement in language may be associated with higher verbal short-term memory and receptive language at baseline. Those with working memory impairments were among those showing the fewest improvements across measures. Conclusions: Narrative-based language intervention impacted verbal skills in different ways across individual children with DLD. Implications: Further research is needed to gain an understanding of who benefits most from narrative-based language intervention

Comparing Language Profiles: Children with Specific Language Impairment and Developmental Coordination Disorder

Background: Although it is widely recognized that substantial heterogeneity exists in the cognitive profiles of children with Developmental Coordination Disorder (DCD), very little is known about the language skills of this group. Aims: To compare the language abilities of children with DCD with a group whose language impairment has been well described: children with Specific Language Impairment (SLI). Methods & Procedures: Eleven children with DCD and 11 with SLI completed standardized and non-standardized assessments of vocabulary, grammatical skill, non-word repetition, sentence recall, story retelling, and articulation rate. Performance on the non-standardized measures was compared with a group of typically developing children of the same age. Outcomes & Results: Children with DCD were impaired on tasks involving verbal recall and story retelling. Almost half of those in the DCD group performed similarly to the children with SLI over several expressive language measures, while 18% had deficits in non-word repetition and story retelling only. Poor non-word repetition was observed for both the DCD and the SLI groups. The articulation rate of the children with SLI was slower than that of the DCD group, which was slower than that of typically developing children. Conclusions: Language impairment is a common co-occurring condition in DCD. The language profile of children with either DCD or SLI was similar in the majority of, but not all, cases

Specific language or working memory impairments: A small scale observational study

Study of the developmental relationship between language and working memory skills has only just begun, despite the prominent role of their interdependency in some theoretical accounts of developmental language impairments. Recently, Archibald and Joanisse (2009) identified children with specific language impairment (SLI), or specific working memory impairment (SWMI), or mixed language and working memory impairment (Mixed) based on standardized testing. In the present study, we report a first effort to provide clinical verification of these profiles by describing the social, behavioral, and academic characteristics of individual group members. Two each of children with SLI, SWMI, or Mixed impairments, individually paired with six typically developing classmates, were observed in their classroom, and their teachers completed questionnaires related to communication, working memory, and attention. Children with impairments were distinguished from typically developing children; however, relatively few patterns further distinguished the children with SLI, SWMI, and Mixed impairments. Interestingly, the children with memory impairments were found to have some language-related difficulties, and the children with language impairments, some memory-related difficulties. The limitations of these preliminary findings and future directions are discussed. © The Author(s) 2011