Beyond the phonological deficit: Semantics contributes indirectly to decoding efficiency in children with dyslexia

Lexical Morphology as a Source of Risk and Resilience for Learning to Read With Dyslexia: An fNIRS Investigation

PURPOSE

We examined the neurocognitive bases of lexical morphology in children of varied reading abilities to understand the role of meaning-based skills in learning to read with dyslexia.

METHOD

Children completed auditory morphological and phonological awareness tasks during functional near-infrared spectroscopy neuroimaging. We first examined the relation between lexical morphology and phonological processes in typically developing readers (Study 1, N = 66, Mage = 8.39), followed by a more focal inquiry into lexical morphology processes in dyslexia (Study 2, N = 50, Mage = 8.62).

RESULTS

Typical readers exhibited stronger engagement of language neurocircuitry during the morphology task relative to the phonology task, suggesting that morphological analyses involve synthesizing multiple components of sublexical processing. This effect was stronger for more analytically complex derivational affixes (like + ly) than more semantically transparent free base morphemes (snow + man). In contrast, children with dyslexia exhibited stronger activation during the free base condition relative to derivational affix condition. Taken together, the findings suggest that although children with dyslexia may struggle with derivational morphology, they may also use free base morphemes' semantic information to boost word recognition.

CONCLUSION

This study informs literacy theories by identifying an interaction between reading ability, word structure, and how the developing brain learns to recognize words in speech and print.

SUPPLEMENTAL MATERIAL

https://doi.org/10.23641/asha.25944949.

RAN-related neural-congruency: a machine learning approach toward the study of the neural underpinnings of naming speed

Objective

Naming speed, behaviorally measured via the serial Rapid automatized naming (RAN) test, is one of the most examined underlying cognitive factors of reading development and reading difficulties (RD). However, the unconstrained-reading format of serial RAN has made it challenging for traditional EEG analysis methods to extract neural components for studying the neural underpinnings of naming speed. The present study aims to explore a novel approach to isolate neural components during the serial RAN task that are (a) informative of group differences between children with dyslexia (DYS) and chronological age controls (CAC), (b) improve the power of analysis, and (c) are suitable for deciphering the neural underpinnings of naming speed.

Methods

We propose a novel machine-learning-based algorithm that extracts spatiotemporal neural components during serial RAN, termed RAN-related neural-congruency components. We demonstrate our approach on EEG and eye-tracking recordings from 60 children (30 DYS and 30 CAC), under phonologically or visually similar, and dissimilar control tasks.

Results

Results reveal significant differences in the RAN-related neural-congruency components between DYS and CAC groups in all four conditions.

Conclusion

Rapid automatized naming-related neural-congruency components capture the neural activity of cognitive processes associated with naming speed and are informative of group differences between children with dyslexia and typically developing children.

Significance

We propose the resulting RAN-related neural-components as a methodological framework to facilitate studying the neural underpinnings of naming speed and their association with reading performance and related difficulties.

Increased top-down semantic processing in natural speech linked to better reading in dyslexia

Early research proposed that individuals with developmental dyslexia use contextual information to facilitate lexical access and compensate for phonological deficits. Yet at present there is no corroborating neuro-cognitive evidence. We explored this with a novel combination of magnetoencephalography (MEG), neural encoding and grey matter volume analyses. We analysed MEG data from 41 adult native Spanish speakers (14 with dyslexic symptoms) who passively listened to naturalistic sentences. We used multivariate Temporal Response Function analysis to capture online cortical tracking of both auditory (speech envelope) and contextual information. To compute contextual information tracking we used word-level Semantic Surprisal derived using a Transformer Neural Network language model. We related online information tracking to participants' reading scores and grey matter volumes within the reading-linked cortical network. We found that right hemisphere envelope tracking was related to better phonological decoding (pseudoword reading) for both groups, with dyslexic readers performing worse overall at this task. Consistently, grey matter volume in the superior temporal and bilateral inferior frontal areas increased with better envelope tracking abilities. Critically, for dyslexic readers only, stronger Semantic Surprisal tracking in the right hemisphere was related to better word reading. These findings further support the notion of a speech envelope tracking deficit in dyslexia and provide novel evidence for top-down semantic compensatory mechanisms.

As clear as glass: How figurativeness and familiarity impact simile processing in readers with and without dyslexia

For skilled readers, idiomatic language confers faster access to overall meaning compared with non-idiomatic language, with a processing advantage for figurative over literal interpretation. However, currently very little research exists to elucidate whether atypical readers-such as those with developmental dyslexia-show such a processing advantage for figurative interpretations of idioms, or whether their reading impairment implicates subtle differences in semantic access. We wanted to know whether an initial figurative interpretation of similes, for both typical and dyslexic readers, is dependent on familiarity. Here, we tracked typical and dyslexic readers' eye movements as they read sentences containing similes (e.g., as cold as ice), orthogonally manipulated for novelty (e.g., familiar: as cold as ice, novel: as cold as snow) and figurativeness (e.g., literal: as cold as ice [low temperature], figurative: as cold as ice [emotionally distant]), with figurativeness being defined by the sentence context. Both participant groups exhibited a processing advantage for familiar and figurative similes over novel and literal similes. However, compared with typical readers, participants with dyslexia had greater difficulty processing similes both when they were unfamiliar and when the context biased the simile meaning towards a literal rather than a figurative interpretation. Our findings suggest a semantic processing anomaly in dyslexic readers, which we discuss in light of recent literature on sentence-level semantic processing.

Compensatory role of verbal learning and consolidation in reading and spelling of children with dyslexia

The present study investigated the compensatory role of verbal learning and consolidation in reading and spelling of children with (N = 54) and without dyslexia (N = 36) and the role of verbal learning (learning new verbal information) and consolidation (remember the learned information over time) on the response to a phonics through spelling intervention of children with dyslexia. We also took phonological awareness, rapid automatized naming, verbal working memory, and semantics into account. Results showed that children with dyslexia performed better in verbal learning and equal in verbal consolidation compared to typically developing peers. Regression analyses revealed that verbal learning did not predict reading but did predict spelling ability, across both groups; verbal consolidation did not predict reading, nor spelling. Furthermore, neither verbal learning nor verbal consolidation was related to responsiveness to a phonics through spelling intervention in children with dyslexia. Verbal learning may thus be seen as a compensatory mechanism for spelling before the intervention for children with dyslexia but is beneficial for typically developing children as well.

Semantics impacts response to phonics through spelling intervention in children with dyslexia

We examined the response to a phonics through spelling intervention in 52 children with dyslexia by analyzing their phonological, morphological, and orthographical spelling errors both before and after the intervention whereas their spelling errors before the intervention were compared with those of 105 typically developing spellers. A possible compensatory role of semantics on the intervention effects was also investigated. Results showed that before the intervention, children with dyslexia and the typically developing children both made most morphological errors, followed by orthographic and phonological errors. Within each category, children with dyslexia made more errors than the typically developing children, with differences being largest for phonological errors. Children with dyslexia with better developed semantic representations turned out to make less phonological, morphological, and orthographic errors compared with children with dyslexia with less developed semantic representations. The intervention for children with dyslexia led to a reduction of all error types, mostly of the orthographic errors. In addition, semantics was related to the decline in phonological, morphological, and orthographic spelling errors. This study implicates that semantic stimulation could benefit the spelling development of children at risk for or with dyslexia.

To Name or Not to Name: Eye Movements and Semantic Processing in RAN and Reading

This study examined the well-established relationship between rapid naming and reading. Rapid automatized naming (RAN) has long been demonstrated as a strong predictor of reading abilities. Despite extensive research spanning over 4 decades, the underlying mechanisms of these causes remain a subject of inquiry. The current study investigated the role of eye movements and semantic processing in defining the RAN-reading relationship. The participants in this study were 42 English-speaking undergraduate students at a British university. The materials included a word reading task, two conventional RAN tasks (object and digit), and two RAN-like categorization tasks (object and digit). The results obtained suggested the interdependence between rapid naming and semantic processing. Hierarchical multiple regression analyses revealed that oculomotor control remains an integral part of variability in RAN and reading performance. Taken together, our results suggest that RAN and reading measures are correlated because both require rapid and accurate retrieval of phonological representations, semantic properties of visual stimuli, and stable co-ordination of eye movements.

Longitudinal Relationships Between Reading Abilities, Phonological Awareness, Language Abilities and Executive Functions: Comparison of Low Risk Preterm and Full-Term Children

Different investigations have found that very or extremely (high risk) preterm children show global or specific difficulties in phonological awareness (PA) and reading abilities. Do low risk preterm children, however, exhibit this pattern? Phonological awareness has been considered an important predictor of literacy. Certain executive functions (EFs), and language abilities in turn, have been found to predict PA. The aims of this study are (1) to compare reading abilities of low risk preterm children of different gestational age (GA) groups to those of full-term children, (2) to compare the performance of low risk preterm children of different GA groups to that of full-term children in different EFs, language measures and PA, and (3) to perform a path analysis in order to test a longitudinal model of the relationships between EFs, language abilities, PA and reading. The participants were 108 low risk 4- year-old preterm children, classified into 3 groups of different GAs, and 34 full-term children. The children’s EFs (rapid automatized naming task (RAN), working memory, and inhibition) were assessed at 4 and 5 years of age. Vocabulary comprehension, morphosyntactic production and grammar reception were assessed when the children were 5 years of age, as well as phonemic awareness and syllabic awareness. Finally, reading abilities were assessed when the children were 9 years old. No significant difference between gestational age groups was found on any of the measures taken on EFs, language abilities, phonological awareness, or reading abilities. The path analysis model demonstrates the direct effect of working memory, certain linguistic skills governed by rules (grammar, morphology) and phonological awareness on reading abilities at 9 years of age. The model also shows the mediating role that PA has on the relationship between EFs and language abilities with reading abilities.

Reading comprehension in dyslexic schoolchildren after an intervention program

PURPOSE

To develop a Speech-language Pathology (SLP) program and verify its effects on the reading comprehension of dyslexic students.

METHODS

Participants were eleven 4th and 5th-grade Elementary School students, eight boys and three girls, aged 9-11 years, diagnosed with developmental dyslexia. All individuals underwent the therapeutic program, which was composed of 16 sessions divided into four levels of complexity. A text adapted according to the Cloze technique and reading comprehension and orthography tasks were used in each session. The schoolchildren had their reading comprehension assessed pre- and post-program using a text available at the Test of Reading Comprehension of Expository Texts, adapted for application of the structural Cloze technique without support, according to the Evaluation of Reading Comprehension Levels.

RESULTS

The participants showed better performance in reading comprehension at the post-program assessment not only in the filling of blanks in the text adapted according to the Cloze technique and in the Responses to Reading Comprehension Questions, but also in the level of reading comprehension achieved.

CONCLUSION

The SLP program improved the reading comprehension performance and increased motivation to reading of dyslexic schoolchildren. Both the Cloze technique and the Reading Comprehension Questions were useful tools to develop and identify changes in the reading comprehension of the students assessed. This study is relevant because it prepared and verified the effects of a specific remediation program for schoolchildren with dyslexia by proposing the use of texts adapted according to the Cloze technique combined with other various tasks of reading comprehension and orthography.