The pseudohomophone effect: evidence for an orthography-phonology-conflict

Spelling principles matter: An ERP study investigating the processing of different types of pseudohomophones

Spelling in any writing system is governed by fundamental principles. We examined the processing of two types of pseudohomophones constructed from words whose spellings are based on different principles - on the traditional principle of writing, requiring memorization of their spelling, and on the morphological principle, allowing the determination of their spelling from another word with the same morpheme (root) to examine the dependence of the occurrence of orthography-phonology conflict on spelling principles. Event-related potentials were recorded from 22 volunteers during silent reading. Pseudohomophones based on the morphological principle increased the N400 amplitude, emphasizing semantic and morphological processing importance. The P600 component showed significant effects for differentiating words and pseudohomophones based on the traditional principle, predominantly indicating the involvement of memory and reanalysis processes. Source reconstruction demonstrates that both pseudohomophones activate the left inferior frontal gyrus. However, pseudohomophones based on the traditional principle additionally activate the right and left postcentral gyrus, indicating the involvement of additional areas in the differentiation process. The earlier differences for stimuli based on the morphological principle indicate access to smaller units (morphemes), whereas stimuli based on the traditional principle require whole word processing. Our findings underscore the significant role of spelling principles in orthographic processing.

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.

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.

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.

Influences of First and Second Language Phonology on Spanish Children Learning to Read in English

Children learning to read in two different orthographic systems are exposed to cross-linguistic interferences. We explored the effects of school (Monolingual, Bilingual) and grade (2nd, 4th, and 6th) on phonological activation during a visual word recognition task. Elementary school children from Spain completed a lexical decision task in English. The task included real words and pseudohomophones following Spanish or English phonological rules. Using the mouse-tracking paradigm, we analyzed errors, reaction times, and computer mouse movements. Children in the bilingual school performed better than children in the monolingual school. Children in higher grades performed better than children in lower grades. The interference effect of Spanish phonology was weak and became weaker in higher grades. Spanish children differentiate between first and second language grapheme-to-phoneme correspondences since early on in the educational process. In 6th grade, children from the bilingual school responded better to words and Spanish pseudohomophones, while children from the monolingual school were less distracted by the English pseudohomophones. Children in the bilingual school had stronger inhibition of Spanish (L1) phonology and stronger activation of English (L2) phonology. Instructional method plays an important role on the processing strategies Spanish children rely on when reading in English. School and grade influence the link between orthographic and phonological representations.

Reading without phonology: ERP evidence from skilled deaf readers of Spanish

Reading typically involves phonological mediation, especially for transparent orthographies with a regular letter to sound correspondence. In this study we ask whether phonological coding is a necessary part of the reading process by examining prelingually deaf individuals who are skilled readers of Spanish. We conducted two EEG experiments exploiting the pseudohomophone effect, in which nonwords that sound like words elicit phonological encoding during reading. The first, a semantic categorization task with masked priming, resulted in modulation of the N250 by pseudohomophone primes in hearing but not in deaf readers. The second, a lexical decision task, confirmed the pattern: hearing readers had increased errors and an attenuated N400 response for pseudohomophones compared to control pseudowords, whereas deaf readers did not treat pseudohomophones any differently from pseudowords, either behaviourally or in the ERP response. These results offer converging evidence that skilled deaf readers do not rely on phonological coding during visual word recognition. Furthermore, the finding demonstrates that reading can take place in the absence of phonological activation, and we speculate about the alternative mechanisms that allow these deaf individuals to read competently.

The Effect of Word Predictability on Phonological Activation in Cantonese Reading: A Study of Eye-Fixations and Pupillary Response

This study aimed to investigate the effects of contextual predictability on orthographic and phonological activation during Chinese sentence reading by Cantonese-speaking readers using the error disruption paradigm. Participants' eye fixations and pupil sizes were recorded while they silently read Chinese sentences containing homophonic, orthographic, and unrelated errors. Sentences had varying amounts of contextual information leading up to target words such that some targets were more predictable than others. Results of the fixation time analysis indicated that orthographic effects were significant in first fixation and gaze duration, while phonological effects emerged later in total reading time. However, interactions between predictability and the homophonic condition were found in gaze duration. These results suggest that, while Cantonese readers activate word meanings primarily through orthography in early processing, early phonological activation can occur when facilitated by semantics in high-constraint sentence contexts. Analysis of pupillary response measurements revealed that participants' pupil sizes became larger when they read words containing orthographic errors, suggesting that orthographic error recovery processes significantly increase cognitive load.

Word processing deficits in children with isolated and combined reading and spelling deficits: An ERP-study

Dissociations between reading and spelling deficits are likely to be associated with distinct deficits in orthographic word processing. To specify differences in automatic visual word recognition, the current ERP-study compared children with isolated reading fluency deficits (iRD), isolated spelling deficits (iSD), and combined reading fluency and spelling deficits (cRSD) as well as typically developing (TD) 10-year-olds while performing a variant of the Reicher-Wheeler paradigm: children had to indicate which of two letters occurred at a given position in a previously presented word, legal pseudoword, illegal pseudoword or nonword. Event-related potentials (N200 and N400) associated with sublexical orthographic and lexical orthographic processing as well as phonological word processing were analyzed. All groups showed a word superiority effect, both on the behavioral and the neurophysiological level. Group differences occurred for phonological word processing. TD and iRD groups showed a higher N400 activation for illegal pseudowords than for nonwords, while the two spelling deficit groups showed no activation differences between these two stimuli conditions. The findings suggest that differences in phonological word processing are associated with spelling problems: children with iSD showed reduced sensitivity for phonological word processing, while these deficits were not evident in children with iRD.

Investigating pseudohomophone interference effects in young second-language learners

This study aimed to investigate phonological activation during silent word reading in French adolescents learning English as a second language (L2) at secondary school. Grade 6 and Grade 8 adolescents performed lexical decision tasks in English, where we compared processing of nonwords that were homophonic to real L2 words (i.e., pseudohomophones [PsHs]; e.g., grean) with that of orthographic control pseudowords (OCs; e.g., greun). In Experiment 1, PsHs were constructed so that they sounded like L2 words when using cross-language (L1) grapheme-to-phoneme correspondences (GPCs) only (e.g., grine), whereas PsHs were constructed with within-language (L2) GPCs (e.g., grean) in Experiment 2. Results showed a PsH interference effect as reflected by higher error rates and/or longer rejection times for PsHs compared with OCs whether using within-language or cross-language GPCs and at both grade levels. Evidence of this PsH interference effect was also observed in Experiment 3, which used PsHs that sounded like real L1 words when using L2 GPCs (e.g., droal for the French word drôle [funny in English]). We suggest that young L2 learners automatically activate both L1 and L2 GPCs during L2 silent reading in favor of strong cross-language interactions at the orthography-to-phonology interface. The results are discussed in relation to bilingual and developmental models on visual word recognition.

Verification of nonwords: The baseword frequency effect in children's pseudohomophone reading

In this study, we investigated the baseword frequency effect in children and its implications for models of visual word recognition. The baseword frequency effect reflects the finding that response latencies in the lexical decision task to nonwords derived from high-frequency basewords (e.g., GREAN derived from GREEN) are shorter than for those derived from low-frequency basewords (e.g., SLEAT derived from SLEET). Importantly, the baseword frequency effect presents a challenge to current activation-based models of visual word recognition. One explanation for this effect is that the orthographic representations of high-frequency basewords are easier to access. This allows a quick progression to a verification stage in which the exact spelling of a stimulus is checked, upon which the lexicality decision is then based. The main goal of this study was to investigate whether such a verification mechanism is specifically modulated by the quality of the orthographic lexicon. We tested whether the baseword frequency effect was evident in children's lexical decisions to pseudohomophones (PsH) and whether verification accuracy varied as a function of children's orthographic knowledge. The baseword frequency effect in response latency was observed in both German-speaking adults and children. Children's spelling skills significantly influenced the accuracy of the verification stage in their responses to PsH. These findings imply that verification is an integral part of word reading and thus should be included in computational models of visual word recognition.

Phonological and orthographic coding in deaf skilled readers

Written language is very important in daily life. However, most deaf people do not achieve good reading levels compared to their hearing peers. Previous research has mainly focused on their difficulties when reading in a language with an opaque orthography such as English. In the present study, we investigated visual word recognition of deaf adult skilled readers while reading in Spanish, a language with a transparent orthography, for which obligatory phonological mediation has been claimed. Experiment 1 showed a pseudohomophone inhibitory effect in hearing but not in deaf people. Experiment 2 showed similar orthographic sensitivity, as measured by the transposed-letter effect, for both groups. These results suggest that deaf skilled readers do not rely on phonological mediation, while maintaining the same level of orthographic sensitivity as hearing readers, thus suggesting that the use of phonological coding is not required to access the lexicon and meaning in a language with a transparent orthography.

Drifting through Basic Subprocesses of Reading: A Hierarchical Diffusion Model Analysis of Age Effects on Visual Word Recognition

Reading is one of the most popular leisure activities and it is routinely performed by most individuals even in old age. Successful reading enables older people to master and actively participate in everyday life and maintain functional independence. Yet, reading comprises a multitude of subprocesses and it is undoubtedly one of the most complex accomplishments of the human brain. Not surprisingly, findings of age-related effects on word recognition and reading have been partly contradictory and are often confined to only one of four central reading subprocesses, i.e., sublexical, orthographic, phonological and lexico-semantic processing. The aim of the present study was therefore to systematically investigate the impact of age on each of these subprocesses. A total of 1,807 participants (young, N = 384; old, N = 1,423) performed four decision tasks specifically designed to tap one of the subprocesses. To account for the behavioral heterogeneity in older adults, this subsample was split into high and low performing readers. Data were analyzed using a hierarchical diffusion modeling approach, which provides more information than standard response time/accuracy analyses. Taking into account incorrect and correct response times, their distributions and accuracy data, hierarchical diffusion modeling allowed us to differentiate between age-related changes in decision threshold, non-decision time and the speed of information uptake. We observed longer non-decision times for older adults and a more conservative decision threshold. More importantly, high-performing older readers outperformed younger adults at the speed of information uptake in orthographic and lexico-semantic processing, whereas a general age-disadvantage was observed at the sublexical and phonological levels. Low-performing older readers were slowest in information uptake in all four subprocesses. Discussing these results in terms of computational models of word recognition, we propose age-related disadvantages for older readers to be caused by inefficiencies in temporal sampling and activation and/or inhibition processes.

10 years of BAWLing into affective and aesthetic processes in reading: what are the echoes?

Reading is not only "cold" information processing, but involves affective and aesthetic processes that go far beyond what current models of word recognition, sentence processing, or text comprehension can explain. To investigate such "hot" reading processes, standardized instruments that quantify both psycholinguistic and emotional variables at the sublexical, lexical, inter-, and supralexical levels (e.g., phonological iconicity, word valence, arousal-span, or passage suspense) are necessary. One such instrument, the Berlin Affective Word List (BAWL) has been used in over 50 published studies demonstrating effects of lexical emotional variables on all relevant processing levels (experiential, behavioral, neuronal). In this paper, we first present new data from several BAWL studies. Together, these studies examine various views on affective effects in reading arising from dimensional (e.g., valence) and discrete emotion features (e.g., happiness), or embodied cognition features like smelling. Second, we extend our investigation of the complex issue of affective word processing to words characterized by a mixture of affects. These words entail positive and negative valence, and/or features making them beautiful or ugly. Finally, we discuss tentative neurocognitive models of affective word processing in the light of the present results, raising new issues for future studies.

The neural bases of the pseudohomophone effect: Phonological constraints on lexico-semantic access in reading

We investigated phonological processing in normal readers to answer the question to what extent phonological recoding is active during silent reading and if or how it guides lexico-semantic access. We addressed this issue by looking at pseudohomophone and baseword frequency effects in lexical decisions with event-related functional magnetic resonance imaging (fMRI). The results revealed greater activation in response to pseudohomophones than for well-controlled pseudowords in the left inferior/superior frontal and middle temporal cortex, left insula, and left superior parietal lobule. Furthermore, we observed a baseword frequency effect for pseudohomophones (e.g., FEAL) but not for pseudowords (e.g., FEEP). This baseword frequency effect was qualified by activation differences in bilateral angular and left supramarginal, and bilateral middle temporal gyri for pseudohomophones with low- compared to high-frequency basewords. We propose that lexical decisions to pseudohomophones involves phonology-driven lexico-semantic activation of their basewords and that this is converging neuroimaging evidence for automatically activated phonological representations during silent reading in experienced readers.

Frequency and regularity effects in reading are task dependent: Evidence from ERPs

Many theories of visual word processing assume obligatory semantic access and phonological recoding whenever a written word is encountered. However, the relative importance of different reading processes depends on task. The current study uses event related potentials (ERPs) to investigate whether - and, if so, when and how - effects of task modulate how visually-presented words are processed. Participants were presented written words in the context of two tasks, delayed reading aloud and proper name detection. Stimuli varied factorially on lexical frequency and on spellingto-sound regularity, while controlling for other lexical variables. Effects of both lexical frequency and regularity were modulated by task. Lexical frequency modulated N400 amplitude, but only in the reading aloud task, whereas spellingto-sound regularity interacted with frequency to modulate the LPC, again only in the reading aloud task. Taken together, these results demonstrate that task demands affect how meaning and sound are generated from written words.

What does the brain of children with developmental dyslexia tell us about reading improvement? ERP evidence from an intervention study

Intervention is key to managing developmental dyslexia (DD), but not all children with DD benefit from treatment. Some children improve (improvers, IMP), whereas others do not improve (non-improvers, NIMP). Neurobiological differences between IMP and NIMP have been suggested, but studies comparing IMP and NIMP in childhood are missing. The present study examined whether ERP patterns change with treatment and differ between IMP and NIMP. We investigated the ERPs of 28 children with DD and 25 control children (CON) while performing a phonological lexical decision (PLD) task before and after a 6-month intervention. After intervention children with DD were divided into IMP (n = 11) and NIMP (n = 17). In the PLD–task children were visually presented with words, pseudohomophones, pseudowords, and false fonts and had to decide whether the presented stimulus sounded like an existing German word or not. Prior to intervention IMP showed higher N300 amplitudes over fronto-temporal electrodes compared to NIMP and CON and N400 amplitudes were attenuated in both IMP and NIMP compared to CON. After intervention N300 amplitudes of IMP were comparable to those of CON and NIMP. This suggests that the N300, which has been related to phonological access of orthographic stimuli and integration of orthographic and phonological representations, might index a compensatory mechanism or precursor that facilitates reading improvement. The N400, which is thought to reflect grapheme-phoneme conversion or the access to the orthographic lexicon increased in IMP from pre to post and was comparable to CON after intervention. Correlations between N300 amplitudes pre, growth in reading ability and N400 amplitudes post indicated that higher N300 amplitudes might be important for reading improvement and increase in N400 amplitudes. The results suggest that children with DD, showing the same cognitive profile might differ regarding their neuronal profile which could further influence reading improvement.

An ERP study of effects of regularity and consistency in delayed naming and lexicality judgment in a logographic writing system

Phonological access is an important component in theories and models of word reading. However, phonological regularity and consistency effects are not clearly separable in alphabetic writing systems. We investigated these effects in Chinese, where the two variables are operationally distinct. In this orthographic system, regularity is defined as the congruence between the pronunciation of a complex character (or phonogram), and that of its phonetic radical, while phonological consistency indexes the proportion of orthographic neighbors that share the same pronunciation as the phonogram. In the current investigation, regularity and consistency were contrasted in an event-related potential (ERP) study using a lexical decision (LD) task and a delayed naming (DN) task with native Chinese readers. ERP results showed that effects of regularity occurred early after stimulus onset and were long-lasting. Regular characters elicited larger N170, smaller P200, and larger N400 compared to irregular characters. In contrast, significant effects of consistency were only seen at the P200 and consistent characters showed a greater P200 than inconsistent characters. Thus, both the time course and the direction of the effects indicated that regularity and consistency operated under different mechanisms and were distinct constructs. Additionally, both of these phonological effects were only found in the DN task and absent in LD, suggesting that phonological access was non-obligatory for LD. The study demonstrated cross-language variability in how phonological information was accessed from print and how task demands could influence this process.

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

The Arabic alphabetical orthographic system has various unique features that include the existence of emphatic phonemic letters. These represent several pairs of letters that share a phonological similarity and use the same parts of the articulation system. The phonological and articulatory similarities between these letters lead to spelling errors where the subject tends to produce a pseudohomophone (PHw) instead of the correct word. Here, we investigated whether or not the unique orthographic features of the written Arabic words modulate early orthographic processes. For this purpose, we analyzed event-related potentials (ERPs) collected from adult skilled readers during an orthographic decision task on real words and their corresponding PHw. The subjects' reaction times (RTs) were faster in words than in PHw. ERPs analysis revealed significant response differences between words and the PHw starting during the N170 and extending to the P2 component, with no difference during processing steps devoted to phonological and lexico-semantic processing. Amplitude and latency differences were found also during the P6 component which peaked earlier for words and where source localization indicated the involvement of the classical left language areas. Our findings replicate some of the previous findings on PHw processing and extend them to involve early orthographical processes.

The time course of reading processes in children with and without dyslexia: an ERP study

The main diagnostic criterion for developmental dyslexia (DD) in transparent orthographies is a remarkable reading speed deficit, which is often accompanied by spelling difficulties. These deficits have been traced back to both deficits in orthographic and phonological processing. For a better understanding of the reading speed deficit in DD it is necessary to clarify which processing steps are degraded in children with DD during reading. In order to address this question the present study used EEG to investigate three reading related ERPs: the N170, N400 and LPC. Twenty-nine children without DD and 52 children with DD performed a phonological lexical decision (PLD)-task, which tapped both orthographic and phonological processing. Children were presented with words, pseudohomophones, pseudowords and false fonts and had to decide whether the presented stimulus sounded like an existing German word or not. Compared to control children, children with DD showed deficits in all the investigated ERPs. Firstly, a diminished mean area under the curve for the word material-false font contrasts in the time window of the N170 was observed, indicating a reduced degree of print sensitivity; secondly, N400 amplitudes, as suggested to reflect the access to the orthographic lexicon and grapheme-phoneme conversion, were attenuated; and lastly, phonological access as indexed by the LPC was degraded in children with DD. Processing differences dependent on the linguistic material in children without DD were observed only in the LPC, suggesting that similar reading processes were adopted independent of orthographic familiarity. The results of this study suggest that effective treatment should include both orthographic and phonological training. Furthermore, more longitudinal studies utilizing the same task and stimuli are needed to clarify how these processing steps and their time course change during reading development.

Systematic influence of gaze position on pupil size measurement: analysis and correction

Cognitive effort is reflected in pupil dilation, but the assessment of pupil size is potentially susceptible to changes in gaze position. This study exemplarily used sentence reading as a stand-in for paradigms that assess pupil size in tasks during which changes in gaze position are unavoidable. The influence of gaze position on pupil size was first investigated by an artificial eye model with a fixed pupil size. Despite its fixed pupil size, the systematic measurements of the artificial eye model revealed substantial gaze-position-dependent changes in the measured pupil size. We evaluated two functions and showed that they can accurately capture and correct the gaze-dependent measurement error of pupil size recorded during a sentence-reading and an effortless z-string-scanning task. Implications for previous studies are discussed, and recommendations for future studies are provided.

A dual-route cascaded model of reading by deaf adults: evidence for grapheme to viseme conversion

There is an ongoing debate whether deaf individuals access phonology when reading, and if so, what impact the ability to access phonology might have on reading achievement. However, the debate so far has been theoretically unspecific on two accounts: (a) the phonological units deaf individuals may have of oral language have not been specified and (b) there seem to be no explicit cognitive models specifying how phonology and other factors operate in reading by deaf individuals. We propose that deaf individuals have representations of the sublexical structure of oral-aural language which are based on mouth shapes and that these sublexical units are activated during reading by deaf individuals. We specify the sublexical units of deaf German readers as 11 "visemes" and incorporate the viseme set into a working model of single-word reading by deaf adults based on the dual-route cascaded model of reading aloud by Coltheart, Rastle, Perry, Langdon, and Ziegler (2001. DRC: A dual route cascaded model of visual word recognition and reading aloud. Psychological Review, 108, 204-256. doi: 10.1037//0033-295x.108.1.204). We assessed the indirect route of this model by investigating the "pseudo-homoviseme" effect using a lexical decision task in deaf German reading adults. We found a main effect of pseudo-homovisemy, suggesting that at least some deaf individuals do automatically access sublexical structure during single-word reading.

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.

In the eye of the listener: pupil dilation elucidates discourse processing

The current study investigated cognitive resource allocation in discourse processing by means of pupil dilation and behavioral measures. Short question-answer dialogs were presented to listeners. Either the context question queried a new information focus in the successive answer, or else the context query was corrected in the answer sentence (correction information). The information foci contained in the answer sentences were either adequately highlighted by prosodic means or not. Participants had to judge the adequacy of the focus prosody with respect to the preceding context question. Prosodic judgment accuracy was higher in the conditions bearing adequate focus prosody than in the conditions with inadequate focus prosody. Latency to peak pupil dilation was longer when new information foci were perceived compared to correction foci. Moreover, for the peak dilation, an interaction of focus type and prosody was found. Post hoc statistical tests revealed that prosodically adequate correction focus positions were processed with smaller peak dilation in comparison to all other dialog conditions. Thus, pupil dilation and results of a principal component analysis suggest an interaction of focus type and focus prosody in discourse processing.