Semantic fluency difficulties in developmental dyslexia and developmental language disorder (DLD): poor semantic structure of the lexicon or slower retrieval processes?

Automatic metaphor processing in developmental dyslexia

INTRODUCTION

Previous research found metaphor impairments with dyslexia; however, it is unclear if difficulties are due to initial activation of the metaphorical meaning or to subsequent discourse integration processes. The study examines the presence of early automatic processing of metaphors in adults with developmental dyslexia, considering the role of executive functions and metaphor familiarity.

METHODS

Using a sentence recall task and a semantic judgment task from the Metaphor Interference Effect (MIE) paradigm, we evaluated two early stages of metaphor comprehension, namely the generation of the figurative meaning and the suppression of the literal meaning. High and low familiar metaphors, and their scrambled counterparts, were aurally presented to participants, who were asked to judge whether sentences were literally true or literally false. Afterwards, they were provided ten minutes to recall the sentences they heard to verify the depth of processing for each type of stimulus. A total of 26 participants with dyslexia were included in the experimental group, and 31 in the control group.

RESULTS

Individuals with dyslexia showed a MIE and an accuracy rate that are similar to participants without dyslexia. Inhibition correlated with the MIE size only for high familiar metaphors, and working memory seemed to play no role in the process. In the recall task, both groups demonstrated a better encoding of the metaphorical sentences compared to scrambled metaphors, but participants with dyslexia recalled less metaphors than did the control group, showing that metaphors are no exception to the limitations in sentence retrieval typically found in dyslexia.

CONCLUSIONS

Our findings suggest that individuals with dyslexia are comparable to participants without dyslexia in their ability to automatically compute metaphorical meanings. Thus, difficulties in metaphor comprehension in people with dyslexia that have been detected in previous studies might depend on meaning construction in context rather than online semantic processing.

Semantic fluency in primary school-age children with vision impairment

PURPOSE

Semantic fluency is potentially a useful tool for vocabulary assessment in children with vision impairment because it contains no visual test stimuli. It is not known whether in the primary school years children with vision impairment perform more poorly on semantic fluency tasks compared to their sighted peers.

METHOD

We compared semantic fluency performance of two groups of 5- to 11-year-old British English speaking children-one group with vision impairment and one without. We also investigated within-group differences in performance, based on severity of vision impairment. We administered one category (animals) to children with vision impairment (n = 45) and sighted children (n = 30). Participants had one minute to respond. Responses were coded for accuracy, error type, clusters, and switches.

RESULT

Correct responses increased with age within each group. Groups did not differ significantly on any outcome measure. Severity of vision impairment did not impact task performance.

CONCLUSION

Results suggested that semantic fluency performance-at least for the category animals-is not different in children with vision impairment compared to sighted children. Findings also suggest that semantic fluency could be a suitable addition to the tools that speech-language pathologists use to assess language abilities in children with vision impairment.

Clustering and Switching in Semantic Verbal Fluency: Their Development and Relationship with Word Productivity in Typically Developing Greek-Speaking Children and Adolescents

Performance in semantic verbal fluency (SVF) tasks, mainly measured by the number of words of a particular semantic category produced within a limited time, is a widely accepted measure of cognitive functioning used in the neuropsychological assessment of children and adults. Two strategic processes, Clustering and Switching (C&S) have been proposed to underlie fluency processes and affect performance in the task. However, few studies have reported on the development of those cognitive strategies and their relationship with word productivity in typically developing children. Even fewer studies have covered a broad developmental period from preschool to adolescence or measured the effect of contextual factors in this relationship. Based on a sample of 472 typically developing Greek-speaking children aged 4;0 to 16;11 years, we investigated the development of SVF performance and reported on the degree to which it is affected by C&S strategies, children's sex, and level of parental education. Results revealed a large effect of age on word productivity and on the use of C&S strategies. Two switching factors (number of clusters and number of switches) and two clustering factors (mean cluster size and a novel measure, maximum cluster size), appeared to be significantly associated with word productivity, with the largest effect being attributed to the two switching factors. C&S factors, together with children's age and parental education, predicted 91.7% of the variance in the SVF score. Children's sex was not found to have a significant effect on either word productivity or C&S strategies. Results are discussed for their theoretical implications on the strategic processes underlying word production in typically developing children.

Sensitivity to Semantic Relationships in U.S. Monolingual English-Speaking Typical Talkers and Late Talkers

PURPOSE

Late talkers (LTs) are a group of children who exhibit delays in language development without a known cause. Although a hallmark of LTs is a reduced expressive vocabulary, little is known about LTs' processing of semantic relations among words in their emerging vocabularies. This study uses an eye-tracking task to compare 2-year-old LTs' and typical talkers' (TTs') sensitivity to semantic relationships among early acquired words.

METHOD

U.S. monolingual English-speaking LTs (n = 21) and TTs (n = 24) completed a looking-while-listening task in which they viewed two images on a screen (e.g., a shirt and a pizza), while they heard words that referred to one of the images (e.g., Look! Shirt!; target-present condition) or a semantically related item (e.g., Look! Hat!; target-absent condition). Children's eye movements (i.e., looks to the target) were monitored to assess their sensitivity to these semantic relationships.

RESULTS

Both LTs and TTs looked longer at the semantically related image than the unrelated image on target-absent trials, demonstrating sensitivity to the taxonomic relationships used in the experiment. There was no significant group difference between LTs and TTs. Both groups also looked more to the target in the target-present condition than in the target-absent condition.

CONCLUSIONS

These results reveal that, despite possessing smaller expressive vocabularies, LTs have encoded semantic relationships in their receptive vocabularies and activate these during real-time language comprehension. This study furthers our understanding of LTs' emerging linguistic systems and language processing skills.

SUPPLEMENTAL MATERIAL

https://doi.org/10.23641/asha.23303987.

Development of an Arabic test for assessment of semantics for the Arabic-speaking children: the Arabic semantic test

Background

Semantics is the study of meaning, and it pertains to the meanings of linguistic expressions such as words, phrases, grammatical forms, and sentences. Studying semantic development for preschool children has several applications in research design, assessment, and intervention. In English and most Indo-European languages, there is a long tradition of examining aspects of child language by computing different developmental indices from spontaneous language samples and by applying different language tests. However, for the Arabic language, these aspects are lacking in this valuable area of research. Thus, this study aimed to develop and standardize a comprehensive test for assessing semantic language development suitable for preschool children in Arabic-speaking countries. The constructed Arabic semantic test (AST) was administered to 120 typically developed Egyptian Arabic-speaking children between the ages of 2 to ≤ 4 years divided into 4 age groups, with a 6-month age interval between each group. Children’s responses were statistically analyzed to assess the test’s validity and reliability. Ranks of percentiles were calculated to describe the semantic language development in preschool Egyptian Arabic-speaking children.

Results

A statistically significant difference was found over the scores of the Arabic semantic test in both receptive and expressive aspects of semantics among the 4 participating age groups. Semantic growth was positively correlated to the chronological age of the participating children, with good validity and reliability of the test.

Conclusions

The Arabic semantic test is a valid and reliable test that can be applied to assess semantic development among preschool Arabic-speaking children.

Language and executive function skills as predictors of semantic fluency performance in pre-school children

Purpose: To explore how language and executive function skills of pre-school-aged children contribute to semantic fluency (a form of verbal fluency) performance. This study investigated effect of age and contribution of vocabulary and executive function on qualitative aspects of the semantic fluency task.Method: Forty typically developing Australian-English-speaking pre-school children, aged 4;0-5;11 (mean age = 55.5 months, SD = 5.21) participated. Eight assessment tasks were presented in random order examining semantic fluency, vocabulary knowledge and executive function. Hierarchical multiple regression analyses determined the extent to which measures of executive function and vocabulary accounted for fluency (number of words correctly produced) and qualitative aspects of the semantic fluency task (number of clusters, number of clustered words, number of switches).Result: While executive function and vocabulary were positively correlated with fluency and all qualitative measures of semantic fluency performance, they were not significant predictors of any aspect of task performance. Age and vocabulary were the only significant predictors of fluency, number of words clustered, and number of switches. Performance on these tasks was strongly related to vocabulary and automated retrieval processes.Conclusion: Pre-school children do not predominantly rely on executive function during semantic fluency. The influence that vocabulary has on semantic fluency task performance outweighs that accounted for by age.

Written Language Production in Children With Developmental Language Disorder

This study contributes to the cross-linguistic investigation of written language difficulties in children with DLD by reporting new findings from Greek-speaking individuals. Specifically, we investigate the writing performance of children with DLD and compare it to that of a group of typically developing (TD) children, matched for gender and chronological age. The specific orthographic properties of Greek, radically different from those of English, offer a unique opportunity to understand the nature of written language production in DLD. The participants of the study were 62 children, 31 with DLD and 31 TD. Both groups were asked to write a text on a special prompt they were given by the researcher and they were assessed in the total number of words used in text, in the proportion of incorrectly spelt words in text as well as in the use of verbs, nouns, content and function words. Also, the different words and the total number of main and subordinate clauses each of the participants used in their text were counted. The findings of the study showed that the written outputs of the DLD group were poorer in almost all measurements compared to those of their TD peers. We discuss our findings in relation to those reported by other languages, in particular English, and spell out the implications for assessing written language in children with DLD.

Executive Function, Working Memory, and Verbal Fluency in Relation to Non-Verbal Intelligence in Greek-Speaking School-Age Children with Developmental Language Disorder

Developmental Language Disorder (DLD) is often associated with impairments in working memory (WM), executive functions (EF), and verbal fluency. Moreover, increasing evidence shows poorer performance of children with DLD on non-verbal intelligence tests relative to their typically developing (TD) peers. Yet, the degree and generality of relevant difficulties remain unclear. The present study aimed at investigating WM capacity, key EFs and verbal fluency in relation to non-verbal intelligence in Greek-speaking school-age children with DLD, compared to TD peers (8–9 years). To our knowledge, the present study is the first to attempt a systematic relevant assessment with Greek-speaking school-age children, complementing previous studies mostly involving English-speaking participants. The results showed that children with DLD scored lower than TD peers on the non-verbal intelligence measure. Groups did not differ in the inhibition measures obtained (tapping resistance to either distractor or proactive interference), but children with DLD were outperformed by TD peers in the WM capacity, updating, monitoring (mixing cost), and verbal fluency (phonological and semantic) measures. The effects showed limited (in the case of backward digit recall) or no dependence on non-verbal intelligence. Findings are discussed in terms of their theoretical and practical implications as well as in relation to future lines of research.