Feedforward and Feedback Consistency Effects for High- and Low-Frequency Words in Lexical Decision and Naming

Spelling monosyllabic English words

We conducted a megastudy to examine the spelling of American English monosyllables with typewritten responses. We related both sublexical and lexical/semantic factors to spelling accuracy and reaction time (RT) for the first keypress and response duration for spelling 1,856 monophonic monosyllables. We found that (a) each of 13 predictor variables was significantly related to performance for at least one measure, (b) orthographic length was unrelated to the first key RT, but did relate to accuracy and response duration, (c) sound-spelling and spelling-sound consistency was related to performance, and in particular, onset consistency related to accuracy and first key RT, but was unrelated to response duration, (d) contextual diversity was consistently related to performance across all measures, and (e) age of acquisition (AoA) was related to all measures, but was related more to the first key RT than response duration. The results indicate that people begin the spelling process once they identify the first letter, and they continue to process the spelling pattern as the response unfolds. These results are best explained by a parallel-distributed-processing framework.

Orthography-phonology consistency in English: Theory- and data-driven measures and their impact on auditory vs. visual word recognition

Research on orthographic consistency in English words has selectively identified different sub-syllabic units in isolation (grapheme, onset, vowel, coda, rime), yet there is no comprehensive assessment of how these measures affect word identification when taken together. To study which aspects of consistency are more psychologically relevant, we investigated their independent and composite effects on human reading behavior using large-scale databases. Study 1 found effects on adults' naming responses of both feedforward consistency (orthography to phonology) and feedback consistency (phonology to orthography). Study 2 found feedback but no feedforward consistency effects on visual and auditory lexical decision tasks, with the best predictor being a composite measure of consistency across grapheme, rime, OVC, and word-initial letter-phoneme. In Study 3, we explicitly modeled the reading process with forward and backward flow in a bidirectionally connected neural network. The model captured latent dimensions of quasi-regular mapping that explain additional variance in human reading and spelling behavior, compared to the established measures. Together, the results suggest interactive activation between phonological and orthographic word representations. They also validate the role of computational analyses of language to better understand how print maps to sound, and what properties of natural language affect reading complexity.

Intelligent Modeling for In-Home Reading and Spelling Programs

Technology-based in-home reading and spelling programs have the potential to compensate for the lack of sufficient instructions provided at schools. However, the recent COVID-19 pandemic showed the immaturity of the existing remote teaching solutions. Consequently, many students did not receive the necessary instructions. This paper presents a model for developing intelligent reading and spelling programs. The proposed approach is based on an optimization model that includes artificial neural networks and linear regression to maximize the educational value of the pedagogical content. This model is personalized, tailored to the learning ability level of each user. Regression models were developed for estimating the lexical difficulty in the literacy tasks of auditory and visual lexical decision, word naming, and spelling. For building these regression models, 55 variables were extracted from French lexical databases that were used with the data from lexical mega-studies. Forward stepwise analysis was conducted to identify the top 10 most important variables for each lexical task. The results showed that the accuracy of the models (based on root mean square error) reached 88.13% for auditory lexical decision, 89.79% for visual lexical decision, 80.53% for spelling, and 83.86% for word naming. The analysis of the results showed that word frequency was a key predictor for all the tasks. For spelling, the number of irregular phoneme-graphemes was an important predictor. The auditory word recognition depended heavily on the number of phonemes and homophones, while visual word recognition depended on the number of homographs and syllables. Finally, the word length and the consistency of initial grapheme-phonemes were important for predicting the word-naming reaction times.

Using information-theoretic measures to characterize the structure of the writing system: the case of orthographic-phonological regularities in English

It is generally well accepted that proficient reading requires the assimilation of myriad statistical regularities present in the writing system, including in particular the correspondences between words' orthographic and phonological forms. There is considerably less agreement, however, as to how to quantify these regularities. Here we present a comprehensive approach for this quantification using tools from Information Theory. We start by providing a glossary of the relevant information-theoretic metrics, with simplified examples showing their potential in assessing orthographic-phonological regularities. We specifically highlight the flexibility of our approach in quantifying information under different contexts (i.e., context-independent and dependent readings) and in different types of mappings (e.g., orthography-to-phonology and phonology-to-orthography). Then, we use these information-theoretic measures to assess real-world orthographic-phonological regularities of 10,093 mono-syllabic English words and examine whether these measures predict inter-item variability in accuracy and response times using available large-scale datasets of naming and lexical decision tasks. Together, the analyses demonstrate how information-theoretical measures can be used to quantify orthographical-phonological correspondences, and show that they capture variance in reading performance that is not accounted for by existing measures. We discuss the similarities and differences between the current framework and previous approaches as well as future directions towards understanding how the statistical regularities embedded in a writing system impact reading and reading acquisition.

Activation time-course of phonological code in silent word recognition in adult readers with and without dyslexia

In skilled adult readers, reading words is generally assumed to rapidly and automatically activate the phonological code. In adults with dyslexia, despite the main consensus on their phonological processing deficits, little is known about the activation time course of this code. The present study investigated this issue in both populations. Participants' accuracy and eye movements were recorded while they performed a visual lexical decision task in which phonological consistency of written words was manipulated. Readers with dyslexia were affected by phonological consistency during second fixation duration of visual word recognition suggesting a late activation of the phonological code. Regarding skilled readers, no influence of phonological consistency was found when the participants were considered a homogeneous population. However, a different pattern emerged when they were divided into two subgroups according to their phonological and semantic abilities: Those who showed better decoding than semantic skills were affected by phonological consistency at the earliest stage of visual word recognition while those who showed better semantic than decoding skills were not affected by this factor at any processing stage. Overall, the findings suggest that the presence of phonological deficits in readers with dyslexia is associated with a delayed activation of phonological representations during reading. In skilled readers, the contribution of phonology varies with their reading profile, i.e., being phonologically or semantically oriented.

Consistency norms for 37,677 english words

Consistency reflects the mapping between spelling and sound. That is, a word is feedforward consistent if its pronunciation matches that of similarly spelled words, and feedback consistent if its spelling matches that of similar pronounced words. For a quasi-regular language such as English, the study of consistency effects on lexical processing has been limited by the lack of readily accessible norms. In order to improve current methodological resources, feedforward (spelling-to-sound) and feedback (sound-to-spelling) consistency measures for 37,677 English words were computed. The consistency measures developed here are operationalized at the composite level for multisyllabic words, and at different sub-syllabic segments (onset, nucleus, coda, oncleus, and rime) for both monosyllabic and multisyllabic words. These measures constitute the largest database of English consistency norms to be developed, and will be a valuable resource for researchers to explore the effects of consistency on lexical processes, such as word recognition and spelling. The norms are available as supplementary material with this paper.

Is holistic processing of written words modulated by phonology?

Holistic processing, a hallmark of face processing, has been shown for written words, signaled by the word composite effect. Fluent readers find it harder to focus on one half of a written word (e.g., the first syllable of a CV.CV word) while ignoring the other half (e.g., the second syllable), especially when the two halves are aligned rather than misaligned. Given the linguistic nature of written words, in the present study, we examined whether the word composite effect is modulated by phonology. In Experiment 1, participants saw two sequentially presented CV.CV words and had to decide if the left half (first syllable) was the same or not, regardless of the right half. The word pairs were either phonologically consistent (univocal orthography to phonology mapping; e.g., TI is always /ti/ in Portuguese) or inconsistent (orthography can map into different phonological representations; e.g., CA can correspond to /ka/ or /kɐ/). The word composite effect was found for phonologically consistent words but not for phonologically inconsistent words. In Experiment 2, timing of trial events was reduced to test whether the influence of phonology was fast and automatic. Similar to what was found in Experiment 1, the word composite effect was found only for phonologically consistent words. The faster trial events in Experiment 2 rendered it less likely that the influence of phonology in word composite effect is merely a result of strategic processing. These findings suggest that holistic processing of visual words is modulated by fast and automatic activation of lexical phonological representations.

Individual Differences in Phonological Feedback Effects: Evidence for the Orthographic Recoding Hypothesis of Orthographic Learning

Share (1995) has proposed phonological recoding (the translation of letters into sounds) as a self-teaching mechanism through which readers establish complete lexical representations. More recently, McKague et al. (2008) proposed a similar role for orthographic recoding, i.e., feedback from sounds to letters, in building and refining lexical representations. We reasoned that an interaction between feedback consistency measures and spelling ability in a spelling decision experiment would lend support to this hypothesis. In a linear mixed effects logistic regression of accuracy data this interaction was significant. Better spellers but not poorer spellers were immune to feedback effects in deciding if a word is spelled correctly, which is consistent with McKague et al.'s prediction that the impact of phonological feedback on word recognition will diminish when the orthographic representation for an item is fully specified. The study demonstrates the importance of considering individual differences when investigating the role of phonology in reading.

Speed and accuracy of dyslexic versus typical word recognition: an eye-movement investigation

Developmental dyslexia is often characterized by a dual deficit in both word recognition accuracy and general processing speed. While previous research into dyslexic word recognition may have suffered from speed-accuracy trade-off, the present study employed a novel eye-tracking task that is less prone to such confounds. Participants (10 dyslexics and 12 controls) were asked to look at real word stimuli, and to ignore simultaneously presented non-word stimuli, while their eye-movements were recorded. Improvements in word recognition accuracy over time were modeled in terms of a continuous non-linear function. The words' rhyme consistency and the non-words' lexicality (unpronounceable, pronounceable, pseudohomophone) were manipulated within-subjects. Speed-related measures derived from the model fits confirmed generally slower processing in dyslexics, and showed a rhyme consistency effect in both dyslexics and controls. In terms of overall error rate, dyslexics (but not controls) performed less accurately on rhyme-inconsistent words, suggesting a representational deficit for such words in dyslexics. Interestingly, neither group showed a pseudohomophone effect in speed or accuracy, which might call the task-independent pervasiveness of this effect into question. The present results illustrate the importance of distinguishing between speed- vs. accuracy-related effects for our understanding of dyslexic word recognition.

A new lexical card-sorting task for studying fronto-striatal contribution to processing language rules

The role of fronto-striatal regions in processing different language rules such as semantic and (grapho) phonological ones is still under debate. We have recently developed a lexical analog of the Wisconsin card sorting task which measures set-shifting abilities where the visual rules color, number, shape were replaced by three language ones: semantic, rhyme and syllable onset (attack). In the present study we aimed to compare fronto-striatal activations between the different lexical rules that are required for matching the test words to the response ones. Using functional magnetic resonance imaging (fMRI), fourteen healthy, native French-speaking participants were scanned. The results showed that some regions within the brain language network are differentially involved in semantic and phonological processes. Semantic decisions activated significantly the ventrolateral prefrontal cortex, the dorsolateral prefrontal cortex, the fusiform gyrus, the ventral temporal lobe and the caudate nucleus, while phonological decisions produced significant activation in posterior Broca's area (area 44), the temporoparietal junction and motor cortical regions. These findings provide critical support for the existence of a ventral subcortical semantic pathway and a more dorsal phonological stream as proposed by Duffau, Leroy, and Gatignol (2008). Furthermore, we propose that the strong involvement of area 47/12 of the ventrolateral prefrontal cortex and caudate nucleus observed in semantic processing, is not specific to language, but to the fact that a category or a rule has to be retrieved amongst competing ones in memory, similarly to what is observed when planning a set-shift in the original (non-lexical) version of the Wisconsin card sorting task.

Imageability and age of acquisition effects in disyllabic word recognition

Imageability and age of acquisition (AoA) effects, as well as key interactions between these variables and frequency and consistency, were examined via multiple regression analyses for 1,936 disyllabic words, using reaction time and accuracy measures from the English Lexicon Project. Both imageability and AoA accounted for unique variance in lexical decision and naming reaction time performance. In addition, across both tasks, AoA and imageability effects were larger for low-frequency words than high-frequency words, and imageability effects were larger for later acquired than earlier acquired words. In reading aloud, consistency effects in reaction time were larger for later acquired words than earlier acquired words, but consistency did not interact with imageability in the reaction time analysis. These results provide further evidence that multisyllabic word recognition is similar to monosyllabic word recognition and indicate that AoA and imageability are valid predictors of word recognition performance. In addition, the results indicate that meaning exerts a larger influence in the reading aloud of multisyllabic words than monosyllabic words. Finally, parallel-distributed-processing approaches provide a useful theoretical framework to explain the main effects and interactions.

Interpreting chicken-scratch: lexical access for handwritten words

Handwritten word recognition is a field of study that has largely been neglected in the psychological literature, despite its prevalence in society. Whereas studies of spoken word recognition almost exclusively employ natural, human voices as stimuli, studies of visual word recognition use synthetic typefaces, thus simplifying the process of word recognition. The current study examined the effects of handwriting on a series of lexical variables thought to influence bottom-up and top-down processing, including word frequency, regularity, bidirectional consistency, and imageability. The results suggest that the natural physical ambiguity of handwritten stimuli forces a greater reliance on top-down processes, because almost all effects were magnified, relative to conditions with computer print. These findings suggest that processes of word perception naturally adapt to handwriting, compensating for physical ambiguity by increasing top-down feedback.

Neural correlates of orthographic and phonological consistency effects in children

The objective of this study was to examine the neural correlates of phonological inconsistency (relationship of spelling to sound) and orthographic inconsistency (relationship of sound to spelling) in visual word processing using functional magnetic resonance imaging (fMRI). Children (9- to 15-year-old) performed a rhyming and spelling task in which two words were presented sequentially in the visual modality. Consistent with previous studies in adults, higher phonological inconsistency was associated with greater activation in several regions including left inferior frontal gyrus and medial frontal gyrus/anterior cingulate cortex. We additionally demonstrated an effect of orthographic inconsistency in these same areas, suggesting that these regions are involved in the integration of orthographic and phonological information and, with respect to the medial frontal/anterior cingulate, greater demands on executive function. Higher phonological and orthographic consistency was associated with greater activation in precuneus/posterior cingulate cortex, the putative steady state system active during resting, suggesting lower demands on cognitive resources for consistent items. Both consistency effects were larger for the rhyming compared with the spelling task suggesting greater demands of integrating spelling and sound in the former task. Finally, accuracy on the rhyming task was negatively correlated with the consistency effect in left fusiform gyrus. In particular, this region showed insensitivity to consistency in low performers, sensitivity to inconsistency (higher activity) in moderate performers, and sensitivity to inconsistency (high activation) and to consistency (deactivation). In general, these results show that the influence of spelling-sound (and sound-spelling) correspondences on processing in fusiform gyrus develops as a function of skill.

Differential effects of orthographic and phonological consistency in cortex for children with and without reading impairment

One of the central challenges in mastering English is becoming sensitive to consistency from spelling to sound (i.e. phonological consistency) and from sound to spelling (i.e. orthographic consistency). Using functional magnetic resonance imaging (fMRI), we examined the neural correlates of consistency in 9-15-year-old Normal and Impaired Readers during a rhyming task in the visual modality. In line with our previous study [Bolger, D.J., Hornickel, J., Cone, N. E., Burman, D. D., & Booth,J. R. (in press). Neural correlates of orthographic and phonological consistency effects in children. Human Brain Mapping], for Normal Readers, lower phonological and orthographic consistency were associated with greater activation in several regions including bilateral inferior/middle frontal gyri, bilateral anterior cingulate cortex as well as left fusiform gyrus. Impaired Readers activated only bilateral anterior cingulate cortex in response to decreasing consistency. Group comparisons revealed that, relative to Impaired Readers, Normal Readers exhibited a larger response in this network for lower phonological consistency whereas orthographic consistency differences were limited. Lastly, brain-behavior correlations revealed a significant relationship between skill (i.e. Phonological Awareness and non-word decoding) and cortical consistency effects for Impaired Readers in left inferior/middle frontal gyri and left fusiform gyrus. Impaired Readers with higher skill showed greater activation for higher consistency. This relationship was reliably different from that of Normal Readers in which higher skill was associated with greater activation for lower consistency. According to single-route or connectionist models, these results suggest that Impaired Readers with higher skill devote neural resources to representing the mapping between orthography and phonology for higher consistency words, and therefore do not robustly activate this network for lower consistency words.

Spelling consistency affects reading in young Dutch readers with and without dyslexia

Lexical-decision studies with experienced English and French readers have shown that visual-word identification is not only affected by pronunciation inconsistency of a word (i.e., multiple ways to pronounce a spelling body), but also by spelling inconsistency (i.e., multiple ways to spell a pronunciation rime). The aim of this study was to compare the reading behavior of young Dutch readers with dyslexia to the behavior of readers without dyslexia. All students participated in a lexical-decision task in which we presented pronunciation-consistent words and pseudowords. Half of the pronunciation-consistent stimuli were spelling consistent and the other half were spelling inconsistent. All three reader groups, that is, students with dyslexia, age-match students, and reading-match students, read spelling-consistent words faster than spelling-inconsistent words. Overall reading speed of students with dyslexia was similar to that of reading-match students, and was substantially slower than that of age-match students. The results suggest that reading in students with or without dyslexia is similarly affected by spelling inconsistency. Subtle qualitative differences emerged, however, with respect to pseudoword identification. The conclusion was that the findings were best interpreted in terms of a recurrent-feedback model.