Resolving the orthographic ambiguity during visual word recognition in Arabic: an event-related potential investigation

Evaluation of the multiple-deficit hypothesis among dyslexic Arabic-speaking children

This study examined the multiple-deficit hypothesis among Arabic-speaking elementary school students. A total of 90 students, divided into three main groups based on their performance on an Arabic word-reading task: dyslexic (n = 30), regular age-matched (n = 30), and 3rd-grade regular students, who were matched to the dyslexic group in regard to their reading proficiency level (n = 30). Participants underwent a nine-domain Arabic reading experiment that measured accuracy and fluency to evaluate general reading proficiency. The performance of Arabic dyslexic students was significantly worse than age-matched controls, but similar to young matched controls based on the reading level of each cognitive task. Moreover, dyslexic students showed deficits in three or more cognitive functions, depending on severity. This study adds to the limited empirical research on the double-deficit hypothesis and its extension to the multiple-domain model among young Arabic students.

Electrophysiological signatures of spelling sensitivity development from primary school age to adulthood

Recognizing spelling errors is important for correct writing and reading, and develops over an extended period. The neural bases of the development of orthographic sensitivity remain poorly understood. We investigated event-related potentials (ERPs) associated with spelling error recognition when performing the orthographic decision task with correctly spelled and misspelled words in children aged 8-10 years old, early adolescents aged 11-14 years old, and adults. Spelling processing in adults included an early stage associated with the initial recognition of conflict between orthography and phonology (reflected in the N400 time window) and a later stage (reflected in the P600 time window) related to re-checking the spelling. In children 8-10 years old, there were no differences in ERPs to correct and misspelled words; in addition, their behavioral scores were worse than those of early adolescents, implying that the ability to quickly recognize the correct spelling is just beginning to develop at this age. In early adolescents, spelling recognition was reflected only at the later stage, corresponding to the P600 component. At the behavioral level, they were worse than adults at recognizing misspelled words. Our data suggest that orthographic sensitivity can develop beyond 14 years.

Neural Specialization for English and Arabic Print in Early Readers

Learning to read requires the specialization of a region in the left fusiform gyrus known as the visual word form area (VWFA). This region, which initially responds to faces and objects, develops specificity for print over a long trajectory of instruction and practice. VWFA neurons may be primed for print because of their pre-literate tuning properties, becoming specialized through top-down feedback mechanisms during learning. However, much of what is known about the VWFA comes from studies of Western orthographies, whose alphabets share common visual characteristics. Far less is known about the development of the VWFA for Arabic, which is a complex orthography and is significantly more difficult to achieve fluency in in reading. In the current study, electroencephalography responses were collected from first grade children in the United Arab Emirates learning to read in both English and Arabic. Children viewed words and false font strings in English and Arabic while performing a vigilance task. The P1 and N1 responses to all stimulus categories were quantified in two occipital and two parietal electrodes as well as the alpha band signal across all four electrodes of interest. Analysis revealed a significantly stronger N1 response to English compared to Arabic and decreased alpha power to Arabic compared to English. These findings suggest a fundamental difference in neural plasticity for these two distinct orthographies, even when instruction is concurrent. Future work is needed to determine whether VWFA specialization for Arabic takes longer than more well-studied orthographies and if differences in reading instruction approaches help accelerate this process.

Top-down modulation of brain responses in spelling error recognition

The task being undertaken can influence orthographic, phonological and semantic processes. In linguistic research, two tasks are most often used: a task requiring a decision in relation to the presented word and a passive reading task which does not require a decision regarding the presented word. The results of studies using these different tasks are not always consistent. This study aimed to explore brain responses associated with the process of recognition of spelling errors, as well as the influence of the task on this process. Event-related potentials (ERPs) were recorded in 40 adults during an orthographic decision task to determine correctly spelled words and words written with errors that did not change the phonology and during the passive reading. During spelling recognition, the early stages up to 100 ms after the stimulus were automatic and did not depend on the requirements of the task. The amplitude of the N1 component (90-160 ms) was greater in the orthographic decision task, but did not depend on the correct spelling of the word. Late word recognition after 350-500 ms was task dependent, but spelling effects were similar across the two tasks: misspelled words evoked an increase in the amplitude of the N400 component related to lexical and semantic processing regardless of the task. In addition, the orthographic decision task modulated spelling effects, this was reflected in an increase in the amplitude of the P2 component (180-260 ms) for correctly spelled words compared with misspelled words. Thus, our results show that spelling recognition involves general lexico-semantic processes independent of the task. Simultaneously, the orthographic decision task modulates the spelling-specific processes necessary to quickly detect conflicts between orthographic and phonological representations of words in memory.

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.

Frequency Effects on Spelling Error Recognition: An ERP Study

Spelling errors are ubiquitous in all writing systems. Most studies exploring spelling errors focused on the phonological plausibility of errors. However, unlike typical pseudohomophones, spelling errors occur in naturally produced written language. We investigated the time course of recognition of the most frequent orthographic errors in Russian (error in an unstressed vowel in the root) and the effect of word frequency on this process. During event-related potentials (ERP) recording, 26 native Russian speakers silently read high-frequency correctly spelled words, low-frequency correctly spelled words, high-frequency words with errors, and low-frequency words with errors. The amplitude of P200 was more positive for correctly spelled words than for misspelled words and did not depend on the frequency of the words. In addition, in the 350–500-ms time window, we found a more negative response for misspelled words than for correctly spelled words in parietal–temporal-occipital regions regardless of word frequency. Considering our results in the context of a dual-route model, we concluded that recognizing misspelled high-frequency and low-frequency words involves common orthographic and phonological processes associated with P200 and N400 components such as whole word orthography processing and activation of phonological representations correspondingly. However, at the 500–700 ms stage (associated with lexical-semantic access in our study), error recognition depends on the word frequency. One possible explanation for these differences could be that at the 500–700 ms stage recognition of high-frequency misspelled and correctly spelled words shifts from phonological to orthographic processes, while low-frequency misspelled words are accompanied by more prolonged phonological activation. We believe these processes may be associated with different ERP components P300 and N400, reflecting a temporal overlap between categorization processes based on orthographic properties for high-frequency words and phonological processes for low-frequency words. Therefore, our results complement existing reading models and demonstrate that the neuronal underpinnings of spelling error recognition during reading may depend on word frequency.

Visual word recognition and vowelization in Arabic: new evidence from lexical decision task performances

The effect of vowelization signs on the process of visual word recognition in Arabic was investigated among 41 native Arab skilled readers with age average of 30.66 ± 9.09. The participants performed a lexical decision task using three types of words and pseudowords; full, partial and non-vowelized. The results showed that for both words and pseudowords, response times were shorter and accuracy levels were higher for the non-vowelized condition compared to the other conditions of vowelization. The results reinforce the argument that automatic lexical processes during word recognition in Arabic orthography might be disturbed by supplementary information such as vowelization.