Reading for sound with dyslexia: Evidence for early orthographic and late phonological integration deficits

Electrophysiological evidence of lexical processing impacted by foreign language reading anxiety

Extensive studies have been conducted on the impact of foreign language reading anxiety on reading, primarily focusing on pedagogy and behavior but lacking electrophysiological evidence. The current study aimed to investigate the influence of foreign language reading anxiety on reading and its underlying mechanisms. The results revealed a negative correlation between foreign language reading anxiety and foreign language reading performance, irrespective of the native language. Adults with low levels of foreign language reading anxiety (LFLRA) demonstrated a significant difference in early lexical component N170 amplitude between foreign and native languages. However, this effect was not observed in adults with high levels of foreign language reading anxiety (HFLRA). In terms of N170 latency, HFLRA showed a longer N170 for the foreign language compared to the native language. Furthermore, the N170 effects were predominantly localized over the left occipitotemporal electrodes. Regarding N400 latency, a significant difference was found in LFLRA individuals between foreign and native language processing, while HFLRA individuals did not exhibit this difference. These findings suggest that HFLRA individuals experience inefficient lexical processing (such as orthography or semantics) during reading in foreign language.

Auditory attention influences trajectories of symbol-speech sound learning in children with and without dyslexia

The acquisition of letter-speech sound correspondences is a fundamental process underlying reading development, one that could be influenced by several linguistic and domain-general cognitive factors. In the current study, we mimicked the first steps of this process by examining behavioral trajectories of audiovisual associative learning in 110 7- to 12-year-old children with and without dyslexia. Children were asked to learn the associations between eight novel symbols and native speech sounds in a brief training and subsequently read words and pseudowords written in the artificial orthography. We then investigated the influence of auditory attention as one of the putative domain-general factors influencing associative learning. To this aim, we assessed children with experimental measures of auditory sustained selective attention and interference control. Our results showed shallower learning trajectories in children with dyslexia, especially during the later phases of the training blocks. Despite this, children with dyslexia performed similarly to typical readers on the post-training reading tests using the artificial orthography. Better auditory sustained selective attention and interference control skills predicted greater response accuracy during training. Sustained selective attention was also associated with the ability to apply these novel correspondences in the reading tests. Although this result has the limitations of a correlational design, it denotes that poor attentional skills may constitute a risk during the early stages of reading acquisition, when children start to learn letter-speech sound associations. Importantly, our findings underscore the importance of examining dynamics of learning in reading acquisition as well as individual differences in more domain-general attentional factors.

Behavioral and electrophysiological analyses of written word processing in spoken and literary Arabic: New insights into the diglossia question

Diglossia in Arabic describes the existence and the use of two varieties of the same language: spoken Arabic (SA) and literary Arabic (LA). SA, the dialect first spoken by Arabic native speakers, is used in non‐formal situations for everyday conversations, and varies from one region to another in the Arabic world. LA, acquired later in life when the children learn to read and write at school, is used for formal purposes such as media, speeches in public and religious sermons. Previous research showed that, in the auditory modality, SA words are processed faster than LA ones. In the visual modality, written LA words are processed faster than SA ones, the latter comparing with low‐frequency words. This study analysed event‐related potentials (ERPs) during the processing of high‐frequency (LAHF), LA low‐frequency (LALF) and SA high‐frequency words (SAHF) in a visual lexical decision task. Faster reaction times were observed for LAHF, followed by SAHF and then by LALF. ERPs showed a modulation of the early components starting from the P100 component and of the late P600 component, supposedly related to memory processes. These findings, indicating that processing written SAHF words was largely comparable with processing of LALF, are discussed in the context of Arabic diglossia.

Typical and Atypical Development of Visual Expertise for Print as Indexed by the Visual Word N1 (N170w): A Systematic Review

The visual word N1 (N170w) is an early brain ERP component that has been found to be a neurophysiological marker for print expertise, which is a prelexical requirement associated with reading development. To date, no other review has assimilated existing research on reading difficulties and atypical development of processes reflected in the N170w response. Hence, this systematic review synthesized results and evaluated neurophysiological and experimental procedures across different studies about visual print expertise in reading development. Literature databases were examined for relevant studies from 1995 to 2020 investigating the N170w response in individuals with or without reading disorders. To capture the development of the N170w related to reading, results were compared between three different age groups: pre-literate children, school-aged children, and young adults. The majority of available N170w studies (N = 69) investigated adults (n = 31) followed by children (school-aged: n = 21; pre-literate: n = 4) and adolescents (n = 1) while some studies investigated a combination of these age groups (n = 12). Most studies were conducted with German-speaking populations (n = 17), followed by English (n = 15) and Chinese (n = 14) speaking participants. The N170w was primarily investigated using a combination of words, pseudowords, and symbols (n = 20) and mostly used repetition-detection (n = 16) or lexical-decision tasks (n = 16). Different studies posed huge variability in selecting electrode sites for analysis; however, most focused on P7, P8, and O1 sites of the international 10–20 system. Most of the studies in adults have found a more negative N170w in controls than poor readers, whereas in children, the results have been mixed. In typical readers, N170w ranged from having a bilateral distribution to a left-hemispheric dominance throughout development, whereas in young, poor readers, the response was mainly right-lateralized and then remained in a bilateral distribution. Moreover, the N170w latency has varied according to age group, with adults having an earlier onset yet with shorter latency than school-aged and pre-literate children. This systematic review provides a comprehensive picture of the development of print expertise as indexed by the N170w across age groups and reading abilities and discusses theoretical and methodological differences and challenges in the field, aiming to guide future research.

The extraction of orthographic and phonological structure of printed words in adults with dyslexia

The current study investigated the extraction of orthographic and phonological structure of written words in adults with dyslexia. In adults without learning difficulties, Chetail and Content showed that orthographic structure, as determined by the number of vowel letter clusters, influences visual word length estimation. The authors also found a phonological effect determined by the number of syllables of words. In the present study, 22 French-speaking students diagnosed with dyslexia in childhood and 22 students without learning disabilities were compared. All participants performed the task of estimating word length. The pattern of results obtained by Chetail and Content was replicated: length estimates were biased by both the number of syllables and the number of vowel letter clusters. The study showed a significant interaction between phonological bias and group. The phonological effect was less important in students with dyslexia, suggesting reduced sensitivity to phonological parsing in reading. In contrast, the orthographic effect did not differ significantly between groups, suggesting that the sensitivity to the orthographic structure of written words is preserved in students with dyslexia despite their low-quality orthographic representations. We conclude that there is no systematic association between sensitivity to the structure of representations and quality of their content.

A Noteworthy Pathology in Children with Learning Disabilities: Late Latency Response Failure in Central Auditory Processing

OBJECTIVES

This study investigates the cortical auditory pathways in children with and without learning disability (LD).

MATERIALS AND METHODS

A prospective, controlled clinical study was conducted on patients diagnosed with LD and was followed-up for a minimum period of 6 months in the Department of Child and Adolescent Psychiatry were included as study group. The control group comprised of age- and gender-matched healthy individuals. After otolaryngological and psychiatric examination, all participants were tested using pure-tone audiometry, tympanometry, acoustic reflex, and cortical auditory evoked potentials. Test results were evaluated and compared for each group.

RESULTS

The study included a total of 60 children (30 children with LD as study group and 30 healthy children as control group) who met the inclusion criteria. When event-related potentials were taken into consideration, P2 and P300 mean amplitudes for right ears and N1 and P300 mean amplitudes for left ears were significantly lower in study group than those in the control group. Likewise, P2 and P300 mean latency in right ears and P1, N1, and P300 mean latency in left ears were prolonged in study group (p<0.05).

CONCLUSION

Patients with LD may have disorders of the cortical auditory processing even if they have normal hearing screening tests. Pathologies in late-latency evoked potentials may have a role in the etiology of these patients.

Effects of school-based mindfulness training on emotion processing and well-being in adolescents: evidence from event-related potentials

In a non-randomized controlled study, we investigated the efficacy of a school-based mindfulness curriculum delivered by schoolteachers to older secondary school students (16-18 years). We measured changes in emotion processing indexed by P3b event-related potential (ERP) modulations in an affective oddball task using static human faces. ERPs were recorded to happy and sad face oddballs presented in a stimulus stream of frequent faces with neutral expression, before and after 8 weeks of mindfulness training. Whilst the mean amplitude of the P3b, an ERP component typically elicited by infrequent oddballs, decreased between testing sessions in the control group, it remained unchanged in the training group. Significant increases in self-reported well-being and fewer doctor visits for mental health support were also reported in the training group as compared to controls. The observed habituation to emotional stimuli in controls thus contrasted with maintained sensitivity in mindfulness-trained students. These results suggest that in-school mindfulness training for adolescents has scope for increasing awareness of socially relevant emotional stimuli, irrespective of valence, and thus may decrease vulnerability to depression.

Altered patterns of directed connectivity within the reading network of dyslexic children and their relation to reading dysfluency

Reading is a complex cognitive skill subserved by a distributed network of visual and language-related regions. Disruptions of connectivity within this network have been associated with developmental dyslexia but their relation to individual differences in the severity of reading problems remains unclear. Here we investigate whether dysfunctional connectivity scales with the level of reading dysfluency by examining EEG recordings during visual word and false font processing in 9-year-old typically reading children (TR) and two groups of dyslexic children: severely dysfluent (SDD) and moderately dysfluent (MDD) dyslexics. Results indicated weaker occipital to inferior-temporal connectivity for words in both dyslexic groups relative to TRs. Furthermore, SDDs exhibited stronger connectivity from left central to right inferior-temporal and occipital sites for words relative to TRs, and for false fonts relative to both MDDs and TRs. Importantly, reading fluency was positively related with forward and negatively with backward connectivity. Our results suggest disrupted visual processing of words in both dyslexic groups, together with a compensatory recruitment of right posterior brain regions especially in the SDDs during word and false font processing. Functional connectivity in the brain's reading network may thus depend on the level of reading dysfluency beyond group differences between dyslexic and typical readers.

Contributions of Letter-Speech Sound Learning and Visual Print Tuning to Reading Improvement: Evidence from Brain Potential and Dyslexia Training Studies

We use a neurocognitive perspective to discuss the contribution of learning letter-speech sound (L-SS) associations and visual specialization in the initial phases of reading in dyslexic children. We review findings from associative learning studies on related cognitive skills important for establishing and consolidating L-SS associations. Then we review brain potential studies, including our own, that yielded two markers associated with reading fluency. Here we show that the marker related to visual specialization (N170) predicts word and pseudoword reading fluency in children who received additional practice in the processing of morphological word structure. Conversely, L-SS integration (indexed by mismatch negativity (MMN)) may only remain important when direct orthography to semantic conversion is not possible, such as in pseudoword reading. In addition, the correlation between these two markers supports the notion that multisensory integration facilitates visual specialization. Finally, we review the role of implicit learning and executive functions in audiovisual learning in dyslexia. Implications for remedial research are discussed and suggestions for future studies are presented.

ERPs Reveal the Time-Course of Aberrant Visual-Phonological Binding in Developmental Dyslexia

New evidence is accumulating for a deficit in binding visual-orthographic information with the corresponding phonological code in developmental dyslexia. Here, we identify the mechanisms underpinning this deficit using event-related brain potentials (ERPs) in dyslexic and control adult readers performing a letter-matching task. In each trial, a printed letter was presented synchronously with an auditory letter name. Incongruent (mismatched), frequent trials were interleaved with congruent (matched) infrequent target pairs, which participants were asked to report by pressing a button. In critical trials, incongruent letter pairs were mismatched but confusable in terms of their visual or phonological features. Typical readers showed early detection of deviant trials, indicated by larger modulation in the range of the phonological mismatch negativity (PMN) compared with standard trials. This was followed by stronger modulation of the P3b wave for visually confusable deviants and an increased lateralized readiness potential (LRP) for phonological deviants, compared with standards. In contrast, dyslexic readers showed reduced sensitivity to deviancy in the PMN range. Responses to deviants in the P3b range indicated normal letter recognition processes, but the LRP calculation revealed a specific impairment for visual-orthographic information during response selection in dyslexia. In a follow-up experiment using an analogous non-lexical task in the same participants, we found no reading-group differences, indicating a degree of specificity to over-learnt visual-phonological binding. Our findings indicate early insensitivity to visual-phonological binding in developmental dyslexia, coupled with difficulty selecting the correct orthographic code.

Lexical and sub-lexical reading skills and their correlation to clinical symptoms in young Chinese patients with schizophrenia

Patients with schizophrenia often experience severe reading deficits such as oral reading and reading comprehension deficits. However, it is not known whether different types of lexical or sub-lexical components in reading are also impaired. In order to address this issue, the present study had 22 young Chinese patients with schizophrenia and 22 young Chinese normal controls undergo a battery of reading tests, which specifically measures lexical and sub-lexical components of reading in Chinese. The schizophrenic group further underwent Brief Psychiatric Rating Scale (BPRS) in order to ascertain the severity of patients' clinical symptoms. The results showed that compared to the controls, (1) the schizophrenic patients performed significantly poorly in orthographic processing, orthography-phonology mapping, and orthography-semantic mapping tests and further that (2) their performances in orthographic processing, and orthography-semantic mapping skill tests negatively correlated with the BPRS score. Note however that their ability to access their mental lexicon was intact. There is thus a clear need for studies with a larger sample-size and neurobiological measures which would lead to our better understanding of the behavioral as well as the neural relationships between schizophrenic patients, and their reading processing impairments, thus developing effective reading intervention programs for the schizophrenic patients.

Eficácia de um programa de intervenção fonológica em escolares de risco para a dislexia

RESUMO: Objetivo: verificar a eficácia de um programa de intervenção fonológica em escolares de risco para a dislexia. Métodos: participaram desse estudo 40 escolares do 1º ano do ensino fundamental, de ambos os gêneros, com idade entre 5 anos e 11 meses a 6 anos e 7 meses. Os escolares foram divididos em dois grupos: GI (20 escolares sem risco para dislexias) e GII (20 escolares com risco para dislexia), ambos os grupos foram submetidos ao programa de intervenção fonológica, composto por tarefas de identificação dos sons e das letras do alfabeto em sequência e em ordem aleatória, identificação e produção de rima, produção de rima com frases, identificação e manipulação de palavras, identificação e produção de sílabas, segmentação e análise silábica, identificação e segmentação fonêmica, substituição, síntese, análise e discriminação fonêmica. Em situação de pré e pós-testagem, todos os sujeitos desse estudo foram submetidos à aplicação do Protocolo de Avaliação das Habilidades Cognitivo-Liguísticas - versão coletiva e individual. Resultados: na comparação da pré com a pós-testagem do desempenho dos escolares de GI e GII, houve diferença estatística para os subtestes das habilidades de leitura, escrita, consciência fonológica, processamento auditivo e velocidade de processamento, indicando média de desempenho superior para GII na pós-testagem comparada a pré-testagem. Conclusão: o programa de intervenção fonológica foi eficaz para os escolares de risco para a dislexia, pois, possibilitou o desenvolvimento da consciência fonológica por meio do trabalho interventivo, auxiliando na aquisição das habilidades necessárias para o aprendizado da leitura e da escrita.

Crossmodal deficit in dyslexic children: practice affects the neural timing of letter-speech sound integration

A failure to build solid letter-speech sound associations may contribute to reading impairments in developmental dyslexia. Whether this reduced neural integration of letters and speech sounds changes over time within individual children and how this relates to behavioral gains in reading skills remains unknown. In this research, we examined changes in event-related potential (ERP) measures of letter-speech sound integration over a 6-month period during which 9-year-old dyslexic readers (n = 17) followed a training in letter-speech sound coupling next to their regular reading curriculum. We presented the Dutch spoken vowels /a/ and /o/ as standard and deviant stimuli in one auditory and two audiovisual oddball conditions. In one audiovisual condition (AV0), the letter “a” was presented simultaneously with the vowels, while in the other (AV200) it was preceding vowel onset for 200 ms. Prior to the training (T1), dyslexic readers showed the expected pattern of typical auditory mismatch responses, together with the absence of letter-speech sound effects in a late negativity (LN) window. After the training (T2), our results showed earlier (and enhanced) crossmodal effects in the LN window. Most interestingly, earlier LN latency at T2 was significantly related to higher behavioral accuracy in letter-speech sound coupling. On a more general level, the timing of the earlier mismatch negativity (MMN) in the simultaneous condition (AV0) measured at T1, significantly related to reading fluency at both T1 and T2 as well as with reading gains. Our findings suggest that the reduced neural integration of letters and speech sounds in dyslexic children may show moderate improvement with reading instruction and training and that behavioral improvements relate especially to individual differences in the timing of this neural integration.

Lexical and sublexical orthographic processing: an ERP study with skilled and dyslexic adult readers

This ERP study investigated the cognitive nature of the P1-N1 components during orthographic processing. We used an implicit reading task with various types of stimuli involving different amounts of sublexical or lexical orthographic processing (words, pseudohomophones, pseudowords, nonwords, and symbols), and tested average and dyslexic readers. An orthographic regularity effect (pseudowords-nonwords contrast) was observed in the average but not in the dyslexic group. This suggests an early sensitivity to the dependencies among letters in word-forms that reflect orthographic structure, while the dyslexic brain apparently fails to be appropriately sensitive to these complex features. Moreover, in the adults the N1-response may already reflect lexical access: (i) the N1 was sensitive to the familiar vs. less familiar orthographic sequence contrast; (ii) and early effects of the phonological form (words-pseudohomophones contrast) were also found. Finally, the later N320 component was attenuated in the dyslexics, suggesting suboptimal processing in later stages of phonological analysis.

Reduced neural integration of letters and speech sounds in dyslexic children scales with individual differences in reading fluency

The acquisition of letter-speech sound associations is one of the basic requirements for fluent reading acquisition and its failure may contribute to reading difficulties in developmental dyslexia. Here we investigated event-related potential (ERP) measures of letter-speech sound integration in 9-year-old typical and dyslexic readers and specifically test their relation to individual differences in reading fluency. We employed an audiovisual oddball paradigm in typical readers (n = 20), dysfluent (n = 18) and severely dysfluent (n = 18) dyslexic children. In one auditory and two audiovisual conditions the Dutch spoken vowels/a/and/o/were presented as standard and deviant stimuli. In audiovisual blocks, the letter ‘a’ was presented either simultaneously (AV0), or 200 ms before (AV200) vowel sound onset. Across the three children groups, vowel deviancy in auditory blocks elicited comparable mismatch negativity (MMN) and late negativity (LN) responses. In typical readers, both audiovisual conditions (AV0 and AV200) led to enhanced MMN and LN amplitudes. In both dyslexic groups, the audiovisual LN effects were mildly reduced. Most interestingly, individual differences in reading fluency were correlated with MMN latency in the AV0 condition. A further analysis revealed that this effect was driven by a short-lived MMN effect encompassing only the N1 window in severely dysfluent dyslexics versus a longer MMN effect encompassing both the N1 and P2 windows in the other two groups. Our results confirm and extend previous findings in dyslexic children by demonstrating a deficient pattern of letter-speech sound integration depending on the level of reading dysfluency. These findings underscore the importance of considering individual differences across the entire spectrum of reading skills in addition to group differences between typical and dyslexic readers.

Anomalous transfer of syntax between languages

Each human language possesses a set of distinctive syntactic rules. Here, we show that balanced Welsh-English bilinguals reading in English unconsciously apply a morphosyntactic rule that only exists in Welsh. The Welsh soft mutation rule determines whether the initial consonant of a noun changes based on the grammatical context (e.g., the feminine noun cath--"cat" mutates into gath in the phrase y gath--"the cat"). Using event-related brain potentials, we establish that English nouns artificially mutated according to the Welsh mutation rule (e.g., "goncert" instead of "concert") require significantly less processing effort than the same nouns implicitly violating Welsh syntax. Crucially, this effect is found whether or not the mutation affects the same initial consonant in English and Welsh, showing that Welsh syntax is applied to English regardless of phonological overlap between the two languages. Overall, these results demonstrate for the first time that abstract syntactic rules transfer anomalously from one language to the other, even when such rules exist only in one language.

Evidence for a preserved sensitivity to orthographic redundancy and an impaired access to phonological syllables in French developmental dyslexics

To evaluate the orthographic and phonological processing skills of developmental dyslexics, we (a) examined their abilities to exploit properties of orthographic redundancy and (b) tested whether their phonological deficit extends to spelling-to-sound connections for large-grain size units such as syllables. To assess the processing skills in dyslexics, we utilized the illusory conjunction paradigm to investigate the nature of reading units in French dyslexic and control children matched in reading age. In control children, reading units were defined by both orthographic redundancy and phonological syllable information. In dyslexics, however, reading units were defined only by orthographic redundancy. Therefore, despite their impairment in reading acquisition, developmental dyslexics have the ability to encode and exploit letter frequency co-occurrences. In contrast, their access to phonological syllables from letters was impaired, suggesting that their phonological deficit extends to large grain-size phonological units.

Processamento auditivo (central) em crianças com dislexia: avaliação comportamental e eletrofisiológica

OBJETIVO: Comparar o desempenho de crianças com dislexia e grupo controle em testes de processamento auditivo e P300. MÉTODOS: Vinte e dois indivíduos com dislexia (grupo estudo) e 16 indivíduos com desenvolvimento considerado típico (grupo controle) participaram do estudo. Todos os indivíduos foram submetidos aos testes de processamento auditivo (Teste Padrão de Frequência, Dicótico de Dígitos e Fala com Ruído) e o P300. RESULTADOS: Em relação aos testes comportamentais, houve diferença para o Teste Padrão de Frequência e para a orelha esquerda no Teste Dicótico de Dígitos, sendo que o grupo estudo apresentou pior desempenho em ambos os testes. Para o P300, houve diferença entre os grupos em relação aos valores absolutos de amplitude e latência, mas esta não foi significativa. CONCLUSÃO: Os achados sugerem que crianças com dislexia apresentam alteração das habilidades auditivas de processamento temporal e figura-fundo, o que foi evidenciado por meio de testes comportamentais de processamento auditivo. Não houve diferença em relação aos desempenhos de ambos os grupos para o P300.

Dyslexia impairs speech recognition but can spare phonological competence

Dyslexia is associated with numerous deficits to speech processing. Accordingly, a large literature asserts that dyslexics manifest a phonological deficit. Few studies, however, have assessed the phonological grammar of dyslexics, and none has distinguished a phonological deficit from a phonetic impairment. Here, we show that these two sources can be dissociated. Three experiments demonstrate that a group of adult dyslexics studied here is impaired in phonetic discrimination (e.g., ba vs. pa), and their deficit compromises even the basic ability to identify acoustic stimuli as human speech. Remarkably, the ability of these individuals to generalize grammatical phonological rules is intact. Like typical readers, these Hebrew-speaking dyslexics identified ill-formed AAB stems (e.g., titug) as less wordlike than well-formed ABB controls (e.g., gitut), and both groups automatically extended this rule to nonspeech stimuli, irrespective of reading ability. The contrast between the phonetic and phonological capacities of these individuals demonstrates that the algebraic engine that generates phonological patterns is distinct from the phonetic interface that implements them. While dyslexia compromises the phonetic system, certain core aspects of the phonological grammar can be spared.

Electrophysiological evidence for impaired attentional engagement with phonologically acceptable misspellings in developmental dyslexia

Event-related potential (ERP) studies of word recognition have provided fundamental insights into the time-course and stages of visual and auditory word form processing in reading. Here, we used ERPs to track the time-course of phonological processing in dyslexic adults and matched controls. Participants engaged in semantic judgments of visually presented high-cloze probability sentences ending either with (a) their best completion word, (b) a homophone of the best completion, (c) a pseudohomophone of the best completion, or (d) an unrelated word, to examine the interplay of phonological and orthographic processing in reading and the stage(s) of processing affected in developmental dyslexia. Early ERP peaks (N1, P2, N2) were modulated in amplitude similarly in the two groups of participants. However, dyslexic readers failed to show the P3a modulation seen in control participants for unexpected homophones and pseudohomophones (i.e., sentence completions that are acceptable phonologically but are misspelt). Furthermore, P3a amplitudes significantly correlated with reaction times in each experimental condition. Our results showed no sign of a deficit in accessing phonological representations during reading, since sentence primes yielded phonological priming effects that did not differ between participant groups in the early phases of processing. On the other hand, we report new evidence for a deficient attentional engagement with orthographically unexpected but phonologically expected words in dyslexia, irrespective of task focus on orthography or phonology. In our view, this result is consistent with deficiency in reading occurring from the point at which attention is oriented to phonological analysis, which may underlie broader difficulties in sublexical decoding.